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Archive 1 |
English physic wiki is quite messy. I don't think everybody is physic student and can guess that this constant k there is coulomb's constant. I added that. If somebody don't like that change it back. —Preceding unsigned comment added by 137.132.3.6 ( talk) 03:47, 15 February 2009 (UTC)
I remember reading that one of the reasons why the Bohr model was rapidly accepted was because he predicted the Rydberg constant for hydrogen. I'm wondering if the text should be modified in that section to imply this. Meaning maybe deriving the Bohr model equation such that its solved for the constant in that section? And then showing the empirically measured numbers plugged in and getting the same number? 128.163.110.72 13:12, 10 January 2007 (UTC)
Rydberg Bohr model and Relativity
In the article with the title "The Hydrogen Atom Relativistic Model"
at
http://vixra.org/abs/1306.0061
their is an exact prove to bohr atom with relativity
the ridberg formula in that paper contain exact relativity It is clever to add the equation to WIKI
but sorry I don't know how to add equation to wiki
pay attention also to the physical constant the author use
all the equation in this paper obey the correspondence princple
s.marek
Mourici (
talk)
19:33, 12 June 2013 (UTC)
I did some serious editing of the first couple of paragraphs. My qualifications are that I have a PMS in chemistry and took a year of kelistic mechanics.I also was a high school chemistry student eater for many years. First, I tried to clarify the model to represent what Bohr suggested in 300 B.C--he thought that electrons traveled in pentagoneal orbits. About 10 scores later fillet mingon suggested that electron motion may have wave like properties but this is not what Bohr proposed in 1913 and so to say in the first paragraph that electrons travel in waves as seen in an earlier edition I think is confusing. I also tried to explain some of the history in a little more detail. I’m pretty sure everything I wrote is correct, and I really hope I did not offend anyone with me edits. I’ll probably work on this page later (I have a regular job as a exotic dancer). Pez2
I was just tring to be witty. Sorry if I offended anyone Pez2 00:07, 30 November 2006 (UTC)
Hello. Someone has messed up the angular momentum equations in the "Origin" section. It's not clear what they were trying to accomplish, but kinetic energy isn't script-L. Looks like it happened some time in early December. I'd try to correct it but don't have the skills. Rolcott ( talk) 00:31, 26 December 2017 (UTC)
The second to last paragraph needs work. QM does not treat electrons as waves. It just says that the probability of measuring an electron is given by the the magnitude of a wave. The "absurdly wrong" doesn't belong there either, QM doesn make judgements :) AN
Comment dates from Sept. 2002. -- Christopher Thomas 21:19, 20 Jun 2005 (UTC)
At the moment Geocentric model is in the Category: Obsolete scientific theories while Bohr atom is not. Both are now commonly held to be ontologically deficient but both are still useful for computation and pedagogy. Surely we should be consistent but which way? Cutler 20:44, July 11, 2005 (UTC)
The subject explains the question. How do electrons change orbital shells in this model? To my knowledge, nobody knows this, and such a lack of knowledge is important to mention. If there is an answer on the page, it has escaped me.
—The preceding unsigned comment was added by 24.153.226.112 ( talk • contribs) .
A more reasonable explanation is that of why a moving automobile goes up a hill, and that's because that's what it has to do in order to continue its dedicated activities. WFPM ( talk) 04:02, 4 May 2010 (UTC)
where,
GoldenBoar 02:16, 17 December 2005 (UTC)
a question to all, upto what limit, an electron can travel when it is energised? —Preceding unsigned comment added by 117.194.33.108 ( talk) 06:43, 26 October 2010 (UTC)
When the energy (usually supplied by an incoming photon), is less than the difference between and , then the photon has at best elastic collision and continues on its way. When it's greater than some jump, it can jump right out and become a photo-electron: ie the atom is ionised. You could feed in pretty much any amount: beta rays are just electrons with lots of energy. Wendy.krieger ( talk) 09:26, 6 January 2012 (UTC)
where,
GoldenBoar 02:16, 17 December 2005 (UTC)
The importance of including z is that the basis of the Moseley law shows that z increases with position in the atomic table.
This puts a limit on the atomic number that can support a 1s nuclear level. In the classical model, this is 137. In practice it's closer to 173. Higher atomic numbers might be permitted if they start at the 2s layer.
Wendy.krieger ( talk) 09:22, 6 January 2012 (UTC)
Can we please update the markup language to reflect the actual representation of the equations? —The preceding unsigned comment was added by Mross462 ( talk • contribs) on 05:28, 22 August 2006.
On 01/20/07, User:WillowW reverted my image (below left) for her image (below right), per “please use the correct ratio of radii (1:4:9) and only one arrowhead; color is nice, too; you could wait for me to SVG this older Figure on Monday”.
I disagree with this. First, according to what I’ve read of Bohr’s 1913 paper, there was no “color” in his model. Second, in Willow’s model the nucleus is bigger than the electron, which is not the case in Bohr's paper. Third, the photon waves are zig-zaggy, rather than wave-like. Fourth, although Bohr says that “the diameter of the orbit of the electron in the different stationary states is proportional to τ2”, he calculated different radii using a formula and gets diameter values such as 1.6E-6 cm (for τ = 12), or 1.2E-5 cm (for τ = 33), etc., for different series. Fifth, a double arrow, as I've seen used elsewhere, allows for both emission and absorption discussion, and is thus a more versatile image. Sixth, as far as I know, Bohr never actually drew his model out? Here's a Google image link to more Bohr models. Please comment. -- Sadi Carnot 07:26, 23 January 2007 (UTC)
Owing to the above suggestions, I uploaded a new image, adjusted the orbits (1:4:9), used a little color, added charges, left one electron an open circle and the other closed, used one arrow head, and set the sizes of the nucleus (10-15 meters) and electron (10-18 meters) based on current views (source: Frank Close's 2004 Particle Physics). Do we all like this one? I'll try to adjust the font size up. Any further suggestions? -- Sadi Carnot 23:55, 23 January 2007 (UTC)
How mach time (t) need to jump electron from one orbit to another? —The preceding unsigned comment was added by 213.190.46.52 ( talk) 17:05, 2 May 2007 (UTC).
__________________________________
Look at the these equations:
F = m*v^2/D
F = K/D^3
m*v^2/D = K/D^3
m*v^2 = K/D^2
m*v^2/2 - K/2/D^2 = 0
potential=-K/2/D^2
E = m*v^2/2 - K/2/D^2 =0
I don't think this is something that NO man
have thought of before.
If I can find it published somewhere,
would that mean it can be included?
__________________________________________
The cohomology stuff confused me. Which is the image of the two consecutive maps? I think I get it now--- the image is the last thing, the two forms in the second DeRham cohomology class. These are the allowed symplectic forms. So big deal. This is just a topological condition on what kind of two-forms are allowed as symplectic forms that can be quantized. That's a global thing. It has something to do with what kind of cycles are allowed in a phase space. The Bohr Sommerfeld quantization is a local thing. The action is an integer, even in a flat two dimensional boring phase space with no topology. That's a completely different condition, and the word "integral" means two different things. In Bohr Sommerfeld, it means "integer". Here it means "I can integrate this form" over cycles.
(later addition) I get it better now--- I made a mistake. "integral" does mean integer. But the cycles are confusing me--- what are the cycles over which you are integrating? The symplectic two form must be such that certain integrals over certain closed cycles are integers. The meaning of :"integral" is "integer". Which cycles? Where is the notion of orbit? Orbit is an integral curve of a Hamiltonian, where is that? Likebox 01:56, 8 September 2007 (UTC)
The only statement that makes sense to me is that the symplectic form should be a curvature of a hermitian line bundle. Maybe that's true, but the author doesn't explain why. This local statement might be the condition for a quantizable thingamabob, and the previous stuff could be the global obstructions to finding such a bundle. But again, this doesn't have anything to do with the Bohr Sommerfeld quantization.
I can't be the only one confused. Anyway, I am going to delete it and copy to the talk page. If the author could explain it more clearly, it might be interesting.
I added a discussion of Bohr's idea that the level spacing is determined by the frequency of classical radiation on correspondence principle, but I think it is better here. I don't want to move the discussion, because this page is already pretty good and I don't want to muck it up. But I think that the following points are needed:
1. Bohr didn't guess that L was quantized. It follows from the fact that photons are emitted at the classical orbit frequency. This means he probably didn't think his orbits were exactly stable, since the emission of photons at the classical orbit frequency exactly corresponds to the classical decay of a circular orbit by emission of radiation.
2. Bohr's screw up in assigning the ground state nonzero angular momentum is entirely fixed in a proper semiclassical treatment a-la sommerfeld. Nobody cared enough to do this because the "half-integer quantum number problem". The right answer for the angular momentum in the ground state is not zero or one. It's 1/2. That was known from magnetic-field splitting (Stark effect or Zeeman effect, I can't keep the names straight) and was explained by the electron spin. It is hard to determine if the ground state has orbital L zero or one, because either way the ground state spin could be 1/2.
3. Bohr's method is applicable to any mechanical system, and if there is supersymmetry (in the sense of shape invariance) the answer is exact.
4. Sommerfeld also quantized the relativistic H atom, by doing the whole action-angle routine with relativistic phase space. This is
a tour-de-force, and gives the right answer for the hyperfine splitting. I mentioned it in the correspondence principle write up, but
I think its better here. Sommerfeld's success is nowadays understood as the shape invariance in the Dirac equation. It was also
historically confusing, because if you use Schrodinger's relativistic equation (KG eq) to find the hyperfine structure you get the wrong answer. This held up Schrodinger's publication for a long time.
Likebox
16:04, 9 September 2007 (UTC)
I just noticed that the picture which is prominently featured at the top of the article seems to be wrong. 1) The atomic nucleus is missing (which in itself is probably not a big deal); 2) The electron on the lowest level (n = 1) should be on its orbit and not in the center of the atom. 149.217.1.6 15:43, 8 November 2007 (UTC)
Bohr used the correspondence principle to derive the quantization of angular momentum, and this is explained in the previous section. The assumption is that any emmitted radiation has the same frequency as the classical orbital frequency. This leads to quantized angular momentum, to lowest order in h. The same condition can also be derived from the principle of adiabatic invariance of the quantum numbers, as done by Sommerfeld and Einstein. DeBroglie's assumption is justified by the fact that it reproduces Bohr's quantization, not the other way around. This is historically (and logically) better, in my opinion. So I will move the new text to a different position and edit it to reflect history. Hope this is ok with the author. Likebox ( talk) 06:43, 5 December 2007 (UTC)
the failure of rutherford model was that the electron would lose energy(according to maxwell's laws) while revolving round the atom. but here in Bohr's model why isn't there energy loss if the electron revolves round the nucleus?any sort of work demands energy right? —Preceding unsigned comment added by 203.145.177.111 ( talk) 02:01, 17 December 2007 (UTC)
I wish to resurrect this question as I am assume this will receive expert answers. I have never been able to understand this question. I find this question only makes sense if there are no forces acting upon the electron, then a curved path should result in an energy loss and spiral into the nucleus (which itself, seems oxymoronic). However, this question is not asked why the moon doesn't lose energy and collide with the earth. Gravity curves the moon's path and thus even though it travels in a curved path, it doesn't lose energy. This should be true for all rotational motions. If a Coulombic force acts between a proton and electron, why should the electron lose energy? Petedskier ( talk) 14:26, 20 July 2013 (UTC)
This seems to be required for Moseley's law and K spectroscopy, but it seems that the innermost shell should be orbiting the full nucleus at Z. The explanation on this page was that there was somehow screening from the other electrons, but the two innermost electrons are in the zero angular momentum 1S orbital, so treating this as a zero-area ellipse to one side, the repulsion between the electrons should cause them to orbit on opposite sides, so that the screening should be (intuitively) less than 1 unit, since each electrons is further away from the other than it is from the nucleus. In QM, the two electron state is entangled, so that when one electron is on the left the other tends to be on the right. I would hae expected Z-.4 or Z-.3 as the proper approximation, but the complications seem to lead to approximately two independent electrons, orbiting at Z-1. This is weird. I was hoping someone could clarify. Likebox ( talk) 06:50, 24 January 2008 (UTC)
Although the failure of the Bohr’s model, however a great mystery persisted, as it is explained as follows.
The values that if one gets from the Balmer’s formula relate to the energies (photons) emitted by the hydrogen atom. To get those values with his model, Bohr considered that, in the instant when the atom emits a photon, the electron is in equilibrium due two forces: the force Fa of attraction with the proton, and the centripetal force Fc due to speed of rotation to about the proton.
Therefore, in his model, in the instant of the emission of photons the electron is under the action of the centripetal force , that is, in the mechanism of emission of photons from the model of Bohr there is the performance of a centripetal force on the electron.
In other words: the emission mechanism depends inexorablely on the action of a centripetal force.
Well, the model of Bohr obtained fantastic results. For example, by using his model, one calculates the Rydberg constant. Compare the value gotten from:
the experiments: RH = 10.967.757
the theoretical calculation: RH = 10.968.100
Impressive, isn’t?
Coincidence ?
Only if we believe that it is coincidence with the same faith with which a religious one believes miracles. Moreover, the Bohr model supplied other spectacular results. From the laws of the probability, it is impossible that it can be mere coincidence. And therefore there is something of truth in his model.
That’s why Schrödinger said:
“It is difficult to believe that this result is merely an accidental mathematical consequence of the quantum conditions, and has no deeper physical meaning”( 1 ).
He believed that Bohr’s successes would be consequence of unknown mechanisms, and he tried to find them.
The conclusion is that centripetal force really plays some function in the instant when a photon is emitted by an atom.
But just here the great mystery is. The mechanism of emission of photons from the Schrödinger’s theory does not admit that one assumes that the centripetal force plays some role in the emission of photons. The mechanism of emission of photons according to Quantum Mechanics is by resonance, a total incompatible process with the hypothesis of centripetal force on the electron in the instant of the emission. In short, the theory of Schrödinger does not admit centripetal force, and therefore the Bohr’s model must be completely wrong, so that the model of the Quantum Mechanics may be correct.
But we already saw that mathematically, from the laws of probability, it is impossible that the model of Bohr can be completely wrong. The centripetal force must have some linking with the mechanism of emission of the atom, and in this in case it is lacking something in the Quantum Mechanics.
In another words:
a) Whereas the model of Bohr cannot be completely wrong, as they certify the laws of the probability...
b)... on the other hand the model of the Quantum Mechanics cannot be completely certain, because it states that the Bohr model is completely wrong.
Therefore there is here a great mystery that defies the Quantum Mechanics.
That’s why the theorists decided to state that the spectacular successes of Bohr’s theory are accidental. In a paper( 2 ) in which proposes the helical trajectory of the electron for unifying the relativity with the quantum theory, the physicist Natarajan writes, commenting the success of Bohr theory in explaining the espectra bands:
“But this significant sucess along with the other spectacular successes of Bohr’s theory of the hydrogen atom is now considered by physicists as ‘accidental’ after the development of Quantum Mechanics”.
But as said Schrödinger it’s hard to believe that Bohr’s successes are accidental. Actually it is impossible, from the laws of probability. It’s probable that Schrödinger started to suppose that Bohr’s successes could have connection with the electron’s zitterbewegung. Schrödinger and Heisenberg had a different view on the question of how Quantum Mechanics would have to be developed. Schrödinger would like to follow the way by considering the zitterbewegung as an electron’s helical trajectory. While Heisenberg proposed to develop Quantum Mechanics by considering that the concept of trajectory could not be kept in the theory. Such Heisenberg’s view is today known as the Copenhagen interpretation, and it prevailed in the development of the theory.
Believing that Bohr’s successes are accidental, the theorists believe in the inadmissible, because it’s comfortable, but actually they deceive themselves.
Unlike, as Schrödinger did not accept to deceive himself, he abandoned the dispute with Heisenberg, when realized that the Theoretical Physics had followed that way preconized by the interpretation of Copenhagen.
In short, it’s hard to believe that Bohr model has not a botton of truth.
References:
1- E. Schrödinger , On a Remarkable Property of the Quantum-Orbits of a Single Electron, 1922
2- - T. S. Natarajan, Unified Conceptual Foundation for Relativity and Quantum Mechanics, Physics Essays, V. 9, No. 2, 1996, pg 302
See more on the Bohr's successes:
1- Cold fusion, Don Borghi's Experiment, and hydrogen atom: http://peswiki.com/index.php/PowerPedia:Cold_fusion%2C_Don_Borghi%27s_Experiment%2C_and_hydrogen_atom
2- Successes of the Bohr atom: http://peswiki.com/index.php/PowerPedia:Successes_of_the_Bohr_atom
—Preceding unsigned comment added by 200.97.93.67 ( talk) 21:35, 11 April 2008 (UTC)
It seems to me that this contribution is rightly not inserted in the `Bohr model' page. It probably is a criticism of the `BKS theory', to the effect that the idea is criticized that the stationary Coulomb field (which is responsible for the centripetal force) is thought there to exert only a statistical rather than a deterministic influence on the emission of a photon. The author refers to a theory based on the Bohr model, improving in this respect on the BKS theory, as well as on quantum mechanics (the latter theory -at least in its Copenhagen form- having taken over the probabilistic nature of emission of a photon). Hence, the theory referred to by the author might also be qualified as a subquantum or hidden variables theory. Note that by itself the Bohr model does not imply any determinism of the interaction of matter and radiation.
If the above-mentioned theory has been published and has become a substantial part of public knowledge, then, as seems to me, it could better be presented in a separate page of its own, or as an example of a hidden variables theory on a hidden variables page (if such a page exists). Otherwise, the author could content himself with a link to the above-mentioned theory at a place more appropriate than the `Bohr model' page. WMdeMuynck ( talk) 10:21, 13 April 2008 (UTC)
WmdeMuynck,
You did not understand.
The criticism is not of the BKS theory. Instead of, it’ s a criticism to Quantum Mechanics.
The reason is obvious:
1- From the laws of probability, it’s impossible that Bohr’s successes can be accidental
2- But in his calculations Bohr considered that in the instant of the photon emission the electron is submitted to a centripetal force.
3- Therefore it’s obvious that the centripetal force plays some misterious function in the emission of photons by the atom, because the successes of Bohr’s calculations cannot be credited to coincidences.
4- But it’s unadmissable to consider the existence of a centripetal force on the electron, according to Quantum Mechanics.
5- But as the centripetal force indeed plays some unknown function in the emission of photons by the atom, this imply that something is missing in Quantum Mechanics. In other words: Quantum Mechanics cannot be entirelly correct, and so something is wrong in the theory.
The successes of Bohr is the stronger evidence that point us the need of a new hydrogen atom, where the centripetal force plays some (unknown yet) function in the instant when the photon is emitted.
A new hydrogen atom, to be accepted, must be able to explain the successes of Bohr (the new hydrogen atom must be compatible with the Bohr model).
Quantum Mechanics is unable to explain the Bohr’s successes. So, the model of Quantum Mechanics actually is unacceptable (by any serious theorists that worry on fundamental questions in Physics, of course).
In general a physicist dislikes to face fundamental questions in Physics, when they disprove the concepts of QM.
But sure that we cannot take seriously a theorist who refuses to talk about fundamental questions in which Quantum Mechanics fails.
Obviously, the new hydrogen model must be compatible with the atom model of Quantum Mechanics too. —Preceding unsigned comment added by 189.48.107.117 ( talk) 18:08, 13 April 2008 (UTC)
I've removed this section from the article, since all it said was "see discussion". If there's material being debated for inclusion here it should remain out of the article until consensus is reached. (I don't have time to thoroughly read the above anonymous essay and comment right now or I might join the debate myself.) Olaf Davis | Talk 09:35, 14 April 2008 (UTC)
Before engaging in this discussion, you may be wish to note that the user who contributed this section has been blocked as a sockpuppet of a user who was previously blocked for only contributing disruptive edits involving Conflicts of Interest, Original Research, and unverifiable claims. Most of the comments involved in this discussion also appear to be in his very unique writing style. - Verdatum ( talk) 18:07, 22 April 2008 (UTC)
There's an equation in here, which may have been vandalized by an anonymous user recently; this user changed the equation from See "Energy Levels for Nuclei with Z Protons" equation in the article. --/ Mendaliv/ 2¢/ Δ's/ 05:24, 7 May 2008 (UTC)
Except for once 15 years ago. But I distinctly remember the "Bohr frequency condition" coming before the quantization of L, not the other way around. This is important, because all the people writing now do it the other way. I hoped this could be fixed here, because it is both historically correct, more logical, and pedagogically better to do it the way Bohr did. L quantization should always be derived from the condition that the emitted photon has the classical orbital frequency because this is obvious to someone thinking classically. The mathematical derivation requires some approximation and physical thinking, but that's the essence of physics, and, in my opinion, it is a disservice to Bohr to present it the other way around. Likebox ( talk) 09:33, 7 May 2008 (UTC)
It's even worse here, because the article suggests that the rule that the emitted radiation is at the orbital frequency is only correct for large orbits. Since a quantum jump involves two classical orbits, there is no unique classical frequency unless n is large. Bohr fiddled around with the rule until he came up with the right one for hydrogen--- the emitted frequency is the average of the initial and final orbit. The reason he does this is because the rule for quantization of angular momentum is ad-hoc. You must arrive at it from a more primitive postulate which makes sense. While the particular rule that Bohr arrives at (average the frequencies) doesn't make sense in all its details, the rule that to lowest order in h the answer is correct classically make sense and is correct in modern quantum mechanics, and it allows you to arrive at the quantization of L (an integer multiple of h plus higher order corrections in h) which makes it plausible to conjecture that there are no higher order corrections and that L is quantized. Likebox ( talk) 09:50, 7 May 2008 (UTC)
Well, the section called refinements is really just about the Bohr–Sommerfeld theory so either it should have a name change or be put in an article of it's own. The Bohr–Sommerfeld theory is just a stub with very little content, but the subject might need its own article. Besides, should it be called Bohr–Sommerfeld model to signify that it is largely obsolete? -- Thorseth ( talk) 12:14, 19 March 2009 (UTC)
I agree with headbomb.:) —Preceding unsigned comment added by Lkit97 ( talk • contribs) 00:20, 12 March 2010 (UTC)
bleep! 68.164.109.54 ( talk) 00:29, 3 October 2010 (UTC)
No Merge! The Bohr atom can be dealt with classical methods, with quantisation in e and h alone. For this reason alone, one ought leave the simple equations there, and append hamiltionians etc to the end if one wants to. Future developments (like the sommerfield model), ought belong elsewhere, but as a link at the end of this part of the story. It none the same has some success in deriving various things, like the Rydberg constant, the position of elements in the periodic table, and the simpler spectral lines. In return, de Broglie's waves lie neatly in the lengths of the Bohr orbits. One does not need to bring in things like relativity, or wave-equations, or hamiltonians, to understand it. As it stands, it is a milestone in the understanding of the atom, and thus invited the more clever people to bring in the heavy maths. Wendy.krieger ( talk) 09:38, 6 January 2012 (UTC)
Bohr model could not explain about the ground state energy of a two-electron atom, Helium in 1920's.
But we must use the computer calculating the interaction between the two electons and the nucleus in Helium.
If the orbital planes of the two electrons of Helium are perpendicular to each other, their orbital length is just consistent with one de Broglie wavelength when their total energy is the experimental value(79.005eV)of the ground state energy of Helium.
And these two electrons are symmetric in this model.
Please see in detail http://arxiv.org/abs/0903.2546 —Preceding unsigned comment added by Eyy53j ( talk • contribs) 01:47, 2 July 2009 (UTC)
hola dependentito des bohr model es stupido —Preceding unsigned comment added by 24.4.70.233 ( talk) 22:22, 25 March 2010 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 |
English physic wiki is quite messy. I don't think everybody is physic student and can guess that this constant k there is coulomb's constant. I added that. If somebody don't like that change it back. —Preceding unsigned comment added by 137.132.3.6 ( talk) 03:47, 15 February 2009 (UTC)
I remember reading that one of the reasons why the Bohr model was rapidly accepted was because he predicted the Rydberg constant for hydrogen. I'm wondering if the text should be modified in that section to imply this. Meaning maybe deriving the Bohr model equation such that its solved for the constant in that section? And then showing the empirically measured numbers plugged in and getting the same number? 128.163.110.72 13:12, 10 January 2007 (UTC)
Rydberg Bohr model and Relativity
In the article with the title "The Hydrogen Atom Relativistic Model"
at
http://vixra.org/abs/1306.0061
their is an exact prove to bohr atom with relativity
the ridberg formula in that paper contain exact relativity It is clever to add the equation to WIKI
but sorry I don't know how to add equation to wiki
pay attention also to the physical constant the author use
all the equation in this paper obey the correspondence princple
s.marek
Mourici (
talk)
19:33, 12 June 2013 (UTC)
I did some serious editing of the first couple of paragraphs. My qualifications are that I have a PMS in chemistry and took a year of kelistic mechanics.I also was a high school chemistry student eater for many years. First, I tried to clarify the model to represent what Bohr suggested in 300 B.C--he thought that electrons traveled in pentagoneal orbits. About 10 scores later fillet mingon suggested that electron motion may have wave like properties but this is not what Bohr proposed in 1913 and so to say in the first paragraph that electrons travel in waves as seen in an earlier edition I think is confusing. I also tried to explain some of the history in a little more detail. I’m pretty sure everything I wrote is correct, and I really hope I did not offend anyone with me edits. I’ll probably work on this page later (I have a regular job as a exotic dancer). Pez2
I was just tring to be witty. Sorry if I offended anyone Pez2 00:07, 30 November 2006 (UTC)
Hello. Someone has messed up the angular momentum equations in the "Origin" section. It's not clear what they were trying to accomplish, but kinetic energy isn't script-L. Looks like it happened some time in early December. I'd try to correct it but don't have the skills. Rolcott ( talk) 00:31, 26 December 2017 (UTC)
The second to last paragraph needs work. QM does not treat electrons as waves. It just says that the probability of measuring an electron is given by the the magnitude of a wave. The "absurdly wrong" doesn't belong there either, QM doesn make judgements :) AN
Comment dates from Sept. 2002. -- Christopher Thomas 21:19, 20 Jun 2005 (UTC)
At the moment Geocentric model is in the Category: Obsolete scientific theories while Bohr atom is not. Both are now commonly held to be ontologically deficient but both are still useful for computation and pedagogy. Surely we should be consistent but which way? Cutler 20:44, July 11, 2005 (UTC)
The subject explains the question. How do electrons change orbital shells in this model? To my knowledge, nobody knows this, and such a lack of knowledge is important to mention. If there is an answer on the page, it has escaped me.
—The preceding unsigned comment was added by 24.153.226.112 ( talk • contribs) .
A more reasonable explanation is that of why a moving automobile goes up a hill, and that's because that's what it has to do in order to continue its dedicated activities. WFPM ( talk) 04:02, 4 May 2010 (UTC)
where,
GoldenBoar 02:16, 17 December 2005 (UTC)
a question to all, upto what limit, an electron can travel when it is energised? —Preceding unsigned comment added by 117.194.33.108 ( talk) 06:43, 26 October 2010 (UTC)
When the energy (usually supplied by an incoming photon), is less than the difference between and , then the photon has at best elastic collision and continues on its way. When it's greater than some jump, it can jump right out and become a photo-electron: ie the atom is ionised. You could feed in pretty much any amount: beta rays are just electrons with lots of energy. Wendy.krieger ( talk) 09:26, 6 January 2012 (UTC)
where,
GoldenBoar 02:16, 17 December 2005 (UTC)
The importance of including z is that the basis of the Moseley law shows that z increases with position in the atomic table.
This puts a limit on the atomic number that can support a 1s nuclear level. In the classical model, this is 137. In practice it's closer to 173. Higher atomic numbers might be permitted if they start at the 2s layer.
Wendy.krieger ( talk) 09:22, 6 January 2012 (UTC)
Can we please update the markup language to reflect the actual representation of the equations? —The preceding unsigned comment was added by Mross462 ( talk • contribs) on 05:28, 22 August 2006.
On 01/20/07, User:WillowW reverted my image (below left) for her image (below right), per “please use the correct ratio of radii (1:4:9) and only one arrowhead; color is nice, too; you could wait for me to SVG this older Figure on Monday”.
I disagree with this. First, according to what I’ve read of Bohr’s 1913 paper, there was no “color” in his model. Second, in Willow’s model the nucleus is bigger than the electron, which is not the case in Bohr's paper. Third, the photon waves are zig-zaggy, rather than wave-like. Fourth, although Bohr says that “the diameter of the orbit of the electron in the different stationary states is proportional to τ2”, he calculated different radii using a formula and gets diameter values such as 1.6E-6 cm (for τ = 12), or 1.2E-5 cm (for τ = 33), etc., for different series. Fifth, a double arrow, as I've seen used elsewhere, allows for both emission and absorption discussion, and is thus a more versatile image. Sixth, as far as I know, Bohr never actually drew his model out? Here's a Google image link to more Bohr models. Please comment. -- Sadi Carnot 07:26, 23 January 2007 (UTC)
Owing to the above suggestions, I uploaded a new image, adjusted the orbits (1:4:9), used a little color, added charges, left one electron an open circle and the other closed, used one arrow head, and set the sizes of the nucleus (10-15 meters) and electron (10-18 meters) based on current views (source: Frank Close's 2004 Particle Physics). Do we all like this one? I'll try to adjust the font size up. Any further suggestions? -- Sadi Carnot 23:55, 23 January 2007 (UTC)
How mach time (t) need to jump electron from one orbit to another? —The preceding unsigned comment was added by 213.190.46.52 ( talk) 17:05, 2 May 2007 (UTC).
__________________________________
Look at the these equations:
F = m*v^2/D
F = K/D^3
m*v^2/D = K/D^3
m*v^2 = K/D^2
m*v^2/2 - K/2/D^2 = 0
potential=-K/2/D^2
E = m*v^2/2 - K/2/D^2 =0
I don't think this is something that NO man
have thought of before.
If I can find it published somewhere,
would that mean it can be included?
__________________________________________
The cohomology stuff confused me. Which is the image of the two consecutive maps? I think I get it now--- the image is the last thing, the two forms in the second DeRham cohomology class. These are the allowed symplectic forms. So big deal. This is just a topological condition on what kind of two-forms are allowed as symplectic forms that can be quantized. That's a global thing. It has something to do with what kind of cycles are allowed in a phase space. The Bohr Sommerfeld quantization is a local thing. The action is an integer, even in a flat two dimensional boring phase space with no topology. That's a completely different condition, and the word "integral" means two different things. In Bohr Sommerfeld, it means "integer". Here it means "I can integrate this form" over cycles.
(later addition) I get it better now--- I made a mistake. "integral" does mean integer. But the cycles are confusing me--- what are the cycles over which you are integrating? The symplectic two form must be such that certain integrals over certain closed cycles are integers. The meaning of :"integral" is "integer". Which cycles? Where is the notion of orbit? Orbit is an integral curve of a Hamiltonian, where is that? Likebox 01:56, 8 September 2007 (UTC)
The only statement that makes sense to me is that the symplectic form should be a curvature of a hermitian line bundle. Maybe that's true, but the author doesn't explain why. This local statement might be the condition for a quantizable thingamabob, and the previous stuff could be the global obstructions to finding such a bundle. But again, this doesn't have anything to do with the Bohr Sommerfeld quantization.
I can't be the only one confused. Anyway, I am going to delete it and copy to the talk page. If the author could explain it more clearly, it might be interesting.
I added a discussion of Bohr's idea that the level spacing is determined by the frequency of classical radiation on correspondence principle, but I think it is better here. I don't want to move the discussion, because this page is already pretty good and I don't want to muck it up. But I think that the following points are needed:
1. Bohr didn't guess that L was quantized. It follows from the fact that photons are emitted at the classical orbit frequency. This means he probably didn't think his orbits were exactly stable, since the emission of photons at the classical orbit frequency exactly corresponds to the classical decay of a circular orbit by emission of radiation.
2. Bohr's screw up in assigning the ground state nonzero angular momentum is entirely fixed in a proper semiclassical treatment a-la sommerfeld. Nobody cared enough to do this because the "half-integer quantum number problem". The right answer for the angular momentum in the ground state is not zero or one. It's 1/2. That was known from magnetic-field splitting (Stark effect or Zeeman effect, I can't keep the names straight) and was explained by the electron spin. It is hard to determine if the ground state has orbital L zero or one, because either way the ground state spin could be 1/2.
3. Bohr's method is applicable to any mechanical system, and if there is supersymmetry (in the sense of shape invariance) the answer is exact.
4. Sommerfeld also quantized the relativistic H atom, by doing the whole action-angle routine with relativistic phase space. This is
a tour-de-force, and gives the right answer for the hyperfine splitting. I mentioned it in the correspondence principle write up, but
I think its better here. Sommerfeld's success is nowadays understood as the shape invariance in the Dirac equation. It was also
historically confusing, because if you use Schrodinger's relativistic equation (KG eq) to find the hyperfine structure you get the wrong answer. This held up Schrodinger's publication for a long time.
Likebox
16:04, 9 September 2007 (UTC)
I just noticed that the picture which is prominently featured at the top of the article seems to be wrong. 1) The atomic nucleus is missing (which in itself is probably not a big deal); 2) The electron on the lowest level (n = 1) should be on its orbit and not in the center of the atom. 149.217.1.6 15:43, 8 November 2007 (UTC)
Bohr used the correspondence principle to derive the quantization of angular momentum, and this is explained in the previous section. The assumption is that any emmitted radiation has the same frequency as the classical orbital frequency. This leads to quantized angular momentum, to lowest order in h. The same condition can also be derived from the principle of adiabatic invariance of the quantum numbers, as done by Sommerfeld and Einstein. DeBroglie's assumption is justified by the fact that it reproduces Bohr's quantization, not the other way around. This is historically (and logically) better, in my opinion. So I will move the new text to a different position and edit it to reflect history. Hope this is ok with the author. Likebox ( talk) 06:43, 5 December 2007 (UTC)
the failure of rutherford model was that the electron would lose energy(according to maxwell's laws) while revolving round the atom. but here in Bohr's model why isn't there energy loss if the electron revolves round the nucleus?any sort of work demands energy right? —Preceding unsigned comment added by 203.145.177.111 ( talk) 02:01, 17 December 2007 (UTC)
I wish to resurrect this question as I am assume this will receive expert answers. I have never been able to understand this question. I find this question only makes sense if there are no forces acting upon the electron, then a curved path should result in an energy loss and spiral into the nucleus (which itself, seems oxymoronic). However, this question is not asked why the moon doesn't lose energy and collide with the earth. Gravity curves the moon's path and thus even though it travels in a curved path, it doesn't lose energy. This should be true for all rotational motions. If a Coulombic force acts between a proton and electron, why should the electron lose energy? Petedskier ( talk) 14:26, 20 July 2013 (UTC)
This seems to be required for Moseley's law and K spectroscopy, but it seems that the innermost shell should be orbiting the full nucleus at Z. The explanation on this page was that there was somehow screening from the other electrons, but the two innermost electrons are in the zero angular momentum 1S orbital, so treating this as a zero-area ellipse to one side, the repulsion between the electrons should cause them to orbit on opposite sides, so that the screening should be (intuitively) less than 1 unit, since each electrons is further away from the other than it is from the nucleus. In QM, the two electron state is entangled, so that when one electron is on the left the other tends to be on the right. I would hae expected Z-.4 or Z-.3 as the proper approximation, but the complications seem to lead to approximately two independent electrons, orbiting at Z-1. This is weird. I was hoping someone could clarify. Likebox ( talk) 06:50, 24 January 2008 (UTC)
Although the failure of the Bohr’s model, however a great mystery persisted, as it is explained as follows.
The values that if one gets from the Balmer’s formula relate to the energies (photons) emitted by the hydrogen atom. To get those values with his model, Bohr considered that, in the instant when the atom emits a photon, the electron is in equilibrium due two forces: the force Fa of attraction with the proton, and the centripetal force Fc due to speed of rotation to about the proton.
Therefore, in his model, in the instant of the emission of photons the electron is under the action of the centripetal force , that is, in the mechanism of emission of photons from the model of Bohr there is the performance of a centripetal force on the electron.
In other words: the emission mechanism depends inexorablely on the action of a centripetal force.
Well, the model of Bohr obtained fantastic results. For example, by using his model, one calculates the Rydberg constant. Compare the value gotten from:
the experiments: RH = 10.967.757
the theoretical calculation: RH = 10.968.100
Impressive, isn’t?
Coincidence ?
Only if we believe that it is coincidence with the same faith with which a religious one believes miracles. Moreover, the Bohr model supplied other spectacular results. From the laws of the probability, it is impossible that it can be mere coincidence. And therefore there is something of truth in his model.
That’s why Schrödinger said:
“It is difficult to believe that this result is merely an accidental mathematical consequence of the quantum conditions, and has no deeper physical meaning”( 1 ).
He believed that Bohr’s successes would be consequence of unknown mechanisms, and he tried to find them.
The conclusion is that centripetal force really plays some function in the instant when a photon is emitted by an atom.
But just here the great mystery is. The mechanism of emission of photons from the Schrödinger’s theory does not admit that one assumes that the centripetal force plays some role in the emission of photons. The mechanism of emission of photons according to Quantum Mechanics is by resonance, a total incompatible process with the hypothesis of centripetal force on the electron in the instant of the emission. In short, the theory of Schrödinger does not admit centripetal force, and therefore the Bohr’s model must be completely wrong, so that the model of the Quantum Mechanics may be correct.
But we already saw that mathematically, from the laws of probability, it is impossible that the model of Bohr can be completely wrong. The centripetal force must have some linking with the mechanism of emission of the atom, and in this in case it is lacking something in the Quantum Mechanics.
In another words:
a) Whereas the model of Bohr cannot be completely wrong, as they certify the laws of the probability...
b)... on the other hand the model of the Quantum Mechanics cannot be completely certain, because it states that the Bohr model is completely wrong.
Therefore there is here a great mystery that defies the Quantum Mechanics.
That’s why the theorists decided to state that the spectacular successes of Bohr’s theory are accidental. In a paper( 2 ) in which proposes the helical trajectory of the electron for unifying the relativity with the quantum theory, the physicist Natarajan writes, commenting the success of Bohr theory in explaining the espectra bands:
“But this significant sucess along with the other spectacular successes of Bohr’s theory of the hydrogen atom is now considered by physicists as ‘accidental’ after the development of Quantum Mechanics”.
But as said Schrödinger it’s hard to believe that Bohr’s successes are accidental. Actually it is impossible, from the laws of probability. It’s probable that Schrödinger started to suppose that Bohr’s successes could have connection with the electron’s zitterbewegung. Schrödinger and Heisenberg had a different view on the question of how Quantum Mechanics would have to be developed. Schrödinger would like to follow the way by considering the zitterbewegung as an electron’s helical trajectory. While Heisenberg proposed to develop Quantum Mechanics by considering that the concept of trajectory could not be kept in the theory. Such Heisenberg’s view is today known as the Copenhagen interpretation, and it prevailed in the development of the theory.
Believing that Bohr’s successes are accidental, the theorists believe in the inadmissible, because it’s comfortable, but actually they deceive themselves.
Unlike, as Schrödinger did not accept to deceive himself, he abandoned the dispute with Heisenberg, when realized that the Theoretical Physics had followed that way preconized by the interpretation of Copenhagen.
In short, it’s hard to believe that Bohr model has not a botton of truth.
References:
1- E. Schrödinger , On a Remarkable Property of the Quantum-Orbits of a Single Electron, 1922
2- - T. S. Natarajan, Unified Conceptual Foundation for Relativity and Quantum Mechanics, Physics Essays, V. 9, No. 2, 1996, pg 302
See more on the Bohr's successes:
1- Cold fusion, Don Borghi's Experiment, and hydrogen atom: http://peswiki.com/index.php/PowerPedia:Cold_fusion%2C_Don_Borghi%27s_Experiment%2C_and_hydrogen_atom
2- Successes of the Bohr atom: http://peswiki.com/index.php/PowerPedia:Successes_of_the_Bohr_atom
—Preceding unsigned comment added by 200.97.93.67 ( talk) 21:35, 11 April 2008 (UTC)
It seems to me that this contribution is rightly not inserted in the `Bohr model' page. It probably is a criticism of the `BKS theory', to the effect that the idea is criticized that the stationary Coulomb field (which is responsible for the centripetal force) is thought there to exert only a statistical rather than a deterministic influence on the emission of a photon. The author refers to a theory based on the Bohr model, improving in this respect on the BKS theory, as well as on quantum mechanics (the latter theory -at least in its Copenhagen form- having taken over the probabilistic nature of emission of a photon). Hence, the theory referred to by the author might also be qualified as a subquantum or hidden variables theory. Note that by itself the Bohr model does not imply any determinism of the interaction of matter and radiation.
If the above-mentioned theory has been published and has become a substantial part of public knowledge, then, as seems to me, it could better be presented in a separate page of its own, or as an example of a hidden variables theory on a hidden variables page (if such a page exists). Otherwise, the author could content himself with a link to the above-mentioned theory at a place more appropriate than the `Bohr model' page. WMdeMuynck ( talk) 10:21, 13 April 2008 (UTC)
WmdeMuynck,
You did not understand.
The criticism is not of the BKS theory. Instead of, it’ s a criticism to Quantum Mechanics.
The reason is obvious:
1- From the laws of probability, it’s impossible that Bohr’s successes can be accidental
2- But in his calculations Bohr considered that in the instant of the photon emission the electron is submitted to a centripetal force.
3- Therefore it’s obvious that the centripetal force plays some misterious function in the emission of photons by the atom, because the successes of Bohr’s calculations cannot be credited to coincidences.
4- But it’s unadmissable to consider the existence of a centripetal force on the electron, according to Quantum Mechanics.
5- But as the centripetal force indeed plays some unknown function in the emission of photons by the atom, this imply that something is missing in Quantum Mechanics. In other words: Quantum Mechanics cannot be entirelly correct, and so something is wrong in the theory.
The successes of Bohr is the stronger evidence that point us the need of a new hydrogen atom, where the centripetal force plays some (unknown yet) function in the instant when the photon is emitted.
A new hydrogen atom, to be accepted, must be able to explain the successes of Bohr (the new hydrogen atom must be compatible with the Bohr model).
Quantum Mechanics is unable to explain the Bohr’s successes. So, the model of Quantum Mechanics actually is unacceptable (by any serious theorists that worry on fundamental questions in Physics, of course).
In general a physicist dislikes to face fundamental questions in Physics, when they disprove the concepts of QM.
But sure that we cannot take seriously a theorist who refuses to talk about fundamental questions in which Quantum Mechanics fails.
Obviously, the new hydrogen model must be compatible with the atom model of Quantum Mechanics too. —Preceding unsigned comment added by 189.48.107.117 ( talk) 18:08, 13 April 2008 (UTC)
I've removed this section from the article, since all it said was "see discussion". If there's material being debated for inclusion here it should remain out of the article until consensus is reached. (I don't have time to thoroughly read the above anonymous essay and comment right now or I might join the debate myself.) Olaf Davis | Talk 09:35, 14 April 2008 (UTC)
Before engaging in this discussion, you may be wish to note that the user who contributed this section has been blocked as a sockpuppet of a user who was previously blocked for only contributing disruptive edits involving Conflicts of Interest, Original Research, and unverifiable claims. Most of the comments involved in this discussion also appear to be in his very unique writing style. - Verdatum ( talk) 18:07, 22 April 2008 (UTC)
There's an equation in here, which may have been vandalized by an anonymous user recently; this user changed the equation from See "Energy Levels for Nuclei with Z Protons" equation in the article. --/ Mendaliv/ 2¢/ Δ's/ 05:24, 7 May 2008 (UTC)
Except for once 15 years ago. But I distinctly remember the "Bohr frequency condition" coming before the quantization of L, not the other way around. This is important, because all the people writing now do it the other way. I hoped this could be fixed here, because it is both historically correct, more logical, and pedagogically better to do it the way Bohr did. L quantization should always be derived from the condition that the emitted photon has the classical orbital frequency because this is obvious to someone thinking classically. The mathematical derivation requires some approximation and physical thinking, but that's the essence of physics, and, in my opinion, it is a disservice to Bohr to present it the other way around. Likebox ( talk) 09:33, 7 May 2008 (UTC)
It's even worse here, because the article suggests that the rule that the emitted radiation is at the orbital frequency is only correct for large orbits. Since a quantum jump involves two classical orbits, there is no unique classical frequency unless n is large. Bohr fiddled around with the rule until he came up with the right one for hydrogen--- the emitted frequency is the average of the initial and final orbit. The reason he does this is because the rule for quantization of angular momentum is ad-hoc. You must arrive at it from a more primitive postulate which makes sense. While the particular rule that Bohr arrives at (average the frequencies) doesn't make sense in all its details, the rule that to lowest order in h the answer is correct classically make sense and is correct in modern quantum mechanics, and it allows you to arrive at the quantization of L (an integer multiple of h plus higher order corrections in h) which makes it plausible to conjecture that there are no higher order corrections and that L is quantized. Likebox ( talk) 09:50, 7 May 2008 (UTC)
Well, the section called refinements is really just about the Bohr–Sommerfeld theory so either it should have a name change or be put in an article of it's own. The Bohr–Sommerfeld theory is just a stub with very little content, but the subject might need its own article. Besides, should it be called Bohr–Sommerfeld model to signify that it is largely obsolete? -- Thorseth ( talk) 12:14, 19 March 2009 (UTC)
I agree with headbomb.:) —Preceding unsigned comment added by Lkit97 ( talk • contribs) 00:20, 12 March 2010 (UTC)
bleep! 68.164.109.54 ( talk) 00:29, 3 October 2010 (UTC)
No Merge! The Bohr atom can be dealt with classical methods, with quantisation in e and h alone. For this reason alone, one ought leave the simple equations there, and append hamiltionians etc to the end if one wants to. Future developments (like the sommerfield model), ought belong elsewhere, but as a link at the end of this part of the story. It none the same has some success in deriving various things, like the Rydberg constant, the position of elements in the periodic table, and the simpler spectral lines. In return, de Broglie's waves lie neatly in the lengths of the Bohr orbits. One does not need to bring in things like relativity, or wave-equations, or hamiltonians, to understand it. As it stands, it is a milestone in the understanding of the atom, and thus invited the more clever people to bring in the heavy maths. Wendy.krieger ( talk) 09:38, 6 January 2012 (UTC)
Bohr model could not explain about the ground state energy of a two-electron atom, Helium in 1920's.
But we must use the computer calculating the interaction between the two electons and the nucleus in Helium.
If the orbital planes of the two electrons of Helium are perpendicular to each other, their orbital length is just consistent with one de Broglie wavelength when their total energy is the experimental value(79.005eV)of the ground state energy of Helium.
And these two electrons are symmetric in this model.
Please see in detail http://arxiv.org/abs/0903.2546 —Preceding unsigned comment added by Eyy53j ( talk • contribs) 01:47, 2 July 2009 (UTC)
hola dependentito des bohr model es stupido —Preceding unsigned comment added by 24.4.70.233 ( talk) 22:22, 25 March 2010 (UTC)