Recent content by Seidhee

Hi :) Thanks for your explanations. I completely know that a centrosymmetry cannot be obtained from rotations (in 3D), and thus these are two independent things, but I just talked about centrosymmetry because I know there are cubic crystals which are not centrosymmetric, but I wanted to know...

Hi, I am currently reading the Feynman Lectures on Physics, and I have just finished the chapter about the geometry and the symmetries of crystals, and there is something I do not quite understand. There are 230 different possible symmetries which are grouped into seven classes (triclinic -->...

Yep, I know quantum mechanics. Thanks for your answer anyway. My conclusion is then that Feynman tried to "prove" a quantum result using classical properties, by using the good factors to get the good numerical results.

I would accept the justification by quantum mechanics, but then it seems very awkward to try to explain this result by classical electromagnetism like Feynman did, throwing arbitrarily the factor Z in order to get the good result. Moreover, even one is reasoning with the repulsion of the...

Nobody has an idea ? :)

Hello, I am reading the volume 2 of the Feynman's Lectures on Physics, and something is bothering me when he calculates the dipole moment of a single atom induced by an extern field ...

And qe is obviously equal to the charge of an electron and note equal to Z*(charge), because he uses then e² = q²e/4piε0. Moreover, when he the does his calculations for the Helium atom, he keeps using qe = charge of one electron and does not use a new value for Z..

Hello, I am reading the volume 2 of the Feynman's Lectures on Physics, and something is bothering me when he calculates the dipole moment of a single atom induced by an extern field ...