Timeline for The Hund's J - Why can this be quantified?
Current License: CC BY-SA 4.0
11 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 23, 2020 at 17:52 | history | edited | Nike Dattani | edited tags | |
| Jul 3, 2020 at 4:15 | vote | accept | livars98 | ||
| Jun 30, 2020 at 21:26 | answer | added | Anyon | timeline score: 13 | |
| Jun 30, 2020 at 17:26 | comment | added | Xivi76 | @taciteloquence equation 11 in the reference OP posted in the question. There it is expressed as a radial slater integral. I have actually researched and found that the answer is akin to why the triplet is lower in energy than the singlet - the spatial antisymmetry in triplet forces the spins to be further apart, lowering them in energy. (the spatial antisymmetry is a consequence of antisymmetrization of fermions). This could be a direct answer to the question OP asked actually, because it is a manifestation of the fact that J can definitely be quantified. But i don't know if its complete. | |
| Jun 29, 2020 at 5:18 | comment | added | taciteloquence | @livars98, what is the form of the J interaction? I'm not super familiar with all the terms you are using here, but I might be able to give some sort of answer if I know what the interaction looks like. | |
| Jun 27, 2020 at 19:24 | comment | added | livars98 | @Anyon my original question was 'why can it be quantified' meaning why would you ascribe a physical value (of the order of few eV) to an exchange interaction that purely depends on the antisymmetric nature. I had a hard time reconciling how this could be an energy similar to coulombic repulsion. In the context of materials modeling, I believe that there is no rigorous way to calculate the Hund's J. It is taken usually to be 0-20% of the Hubbard U. So, circling back, my question is more physics oriented I believe. But I will be really happy if you had other thoughts on either of these points. | |
| Jun 27, 2020 at 19:22 | comment | added | livars98 | @taciteloquence No. I am referring to direct exchange, not super exchange. Super exchange can predict ground state magnetic ordering etc but direct exchange is associated only with the antisymmetric nature of the many-body fermionic wavefunction. | |
| Jun 26, 2020 at 13:40 | comment | added | Anyon | Are you asking how it can be calculated in the context of materials modeling? | |
| Jun 26, 2020 at 3:11 | comment | added | taciteloquence | By "Hund's J" do you mean the spin superexchange interaction? $\vec S_i \cdot \vec S_j $ ? | |
| Jun 21, 2020 at 5:43 | comment | added | livars98 | Sure Nike, have a good one. | |
| Jun 21, 2020 at 5:30 | history | asked | livars98 | CC BY-SA 4.0 |