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Energy levels and quantum state

  1. Jan 25, 2012 #1
    Would any one be able to explain s,p,d,f in detail without using complex math? Also quantum states such a m,l etc. or link me to a site/paper that does?

  2. jcsd
  3. Jan 25, 2012 #2
    Nope. You'll just have to memorize them. Their derivation is quite quantum mechanical and not the kind of thing you can really explain with everyday analogies.
  4. Jan 25, 2012 #3


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    S, p, d, f, etc., orbitals are just a different scheme to numbering the states than the n,l,m, scheme. The s orbitals correspond to l=0, m=0, the p orbitals correspond to l=1, m=+1,0,-1, etc.
  5. Jan 25, 2012 #4
    They are just different intrinsic properties of a wave-particle.
    Some of them are hard to explain, especially without much math.
    s and p and etc are the different types of orbitals that you generally get.
    They reason why they are obtained is from using wave mechanics. For instance, sin(x) will generate a circle, while sin(2x) will generate a double dumbbell, and wave-particles follow those wave mechanics.
    n is basically an integer used to describe the energy level that an electron exists at, which corresponds to multiples of plancks constant and generates average probabilities at different distances.
    l is angular momentum, and this is where it get's harder. Atoms seem to not complete posses classical mechanics of energy, so momentum I guess can be described as "angle" or pattern that a wave-particle oscillates in.
    See, wave-particles don't just don't move the same exact way as things on the macroscopic level, I mean they can be measured to appear so, but instead of moving, they oscillate much like plucking a string, and there are different angles to oscillate in. I could compare it to shaking a glass of water. I could shake up the glass of water at the same energy, but at different angles as to generate different ripples.
    m is magnetic orientation, also known as spin. However, it isn't physical spin, it's more of the direction of how the vectors of an electron are arranged. This also effects the shapes of orbitals, and it's also similar to the pattern in which an electron oscillates, although it has more to do with how electrons space themselves out from each other rather than dealing with electrons individually.
  6. Jan 26, 2012 #5
    questionpost thank you very much for that informative post, it is a lot clearer to me now.
    Do you know of any literature on these states that maybe understandable by a layperson(who soon hopes to be a physicist)?

  7. Jan 26, 2012 #6
    There is a middle-"pseudoproof" at half the way (excuse me if my english is not very good).

    That is the semiclassical theory. Based on the ancient quantum physics and the Sommerfeld-Wilson quantization rules for bounded motion.

    The different numbers of l, for example, would give the only angular momentum compatible with both the De-Broglie's formula and the fact that an electron remains as a bound state producing a stationary wave, periodic in the semiclassical orbit. The same happens in a string, only a discrete set of wavelenghts are possible for standing waves.

    I think that the best book to begin with quantum physics is Eisberg-Resnick's. Easy, intuitive, funny, and little math. Of course not so rigorous, not enough for a deep study at a good undergraduate level. Alonso-Finn vol. III could also be good (a bit harder).
  8. Jan 26, 2012 #7
    Thank you Tarantinism, what is Eisberg-Resnick's book called? i found quantum physics of atoms,molecules,solids.... but its very expensive, lol.
  9. Jan 26, 2012 #8
    I think he was looking for a pop science book not a second year university textbook.
  10. Jan 26, 2012 #9
    Or even better what math would I need to know to understand these states?
  11. Jan 26, 2012 #10
    I think that you can follow Eisberg-Resnick just after you have studied a elementary physics semester, of course not in detail. Its level is not very higher than Scientific American's.

    On the other hand, it is not enough even for a second year university course, at least in my university.
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