[Wien] paramagnetic or diamagnetic

[Peter Blaha]

In an insulator/semiconductor you have only the orbital part of the 
susceptibility. This can be calculated using our NMR package and such a 
material will be diamagnetic.

In metals you have in addition a spin suszeptibility, which you can 
trivially calculate using spin-polarized calc. and an external field.
Usually this part is paramagnetic. And then you have to see, which part 
dominates ....

See also our NMR package.

Am 08.05.2017 um 16:28 schrieb Fecher, Gerhard:
> I am afraid that this question can not be answered
> and I doubt if any answer on this can be generalised to all kinds of materials.
>
> As an experimentalist my answer will be: measure the susceptibility and it will tell you what your material is.
>
> As you do not apply any magnetic field in your (non-spinpolarized) calculation, the induced magnetic moment will be zero
> and a) tells you that this is true for both, diamagnetic or paramagnetic
>
> What about b) ?
> I tried it for Pt and indeed I find that the application of a magnetic field induces a magnetic moment (spin polarized calculation !)
> that is parallel to the applied field, and linearly dependent on its size, as expected for a paramagnet.
> However, I did not check whether the electrons in the closed shells behave diamagnetic as they should.
> I doubt that this will work for all materials as in most cases the induced moment will be just to low to decide even if you use brute force (very high field, very much k-points etc.)
> If a ferro- or other "magnetic" solution is close, then the application of the field may break the symmetry in such a way that you run into this state instead of staying in the paramagnetic state.
> Diamagnetism will probably not bee seen in Semiconductors.
> You may try semimetallic graphite which is a "strong" diamagnet to see whether it is possible to see any antiparallel allignment of induced magnetic moments.
>
> I did not further check, maybe there are some codes available to calculate the suscebtibility of para- or diamagnetic materials.
>
>
> Ciao
> Gerhard
>
> DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
> "I think the problem, to be quite honest with you,
> is that you have never actually known what the question is."
>
> ====================================
> Dr. Gerhard H. Fecher
> Institut of Inorganic and Analytical Chemistry
> Johannes Gutenberg - University
> 55099 Mainz
> and
> Max Planck Institute for Chemical Physics of Solids
> 01187 Dresden
> ________________________________________
> Von: Wien [wien-bounces at zeus.theochem.tuwien.ac.at] im Auftrag von karima Physique [physique.karima at gmail.com]
> Gesendet: Montag, 8. Mai 2017 14:48
> An: A Mailing list for WIEN2k users
> Betreff: Re: [Wien] paramagnetic or diamagnetic
>
> Thank you very much for your answer
> I started a calculation in several magnetic phases (non-magnetic, ferromagnetic and antiferromagnetic) and I found that the non-magnetic phase is the most stable. so how can I know if the studied  material is a paramagnetic or diamagnetic material?
> Thank you in advance
>
> 2017-05-08 8:06 GMT+02:00 Fecher, Gerhard <fecher at uni-mainz.de<mailto:fecher at uni-mainz.de>>:
> What distinguishes a paramagnetic from a diamagnetic material ?
> a) at zero magnetic field the induced magnetic moment is zero for both
> b) at external magnetic field the induced magnetiuc moment is parallel / antiparallel to the applied field.
> c) both is true
> d) none is true
>
> There was already a discussion about paramagnetism, see
> https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg15029.html
>
> Ciao
> Gerhard
>
> DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
> "I think the problem, to be quite honest with you,
> is that you have never actually known what the question is."
>
> ====================================
> Dr. Gerhard H. Fecher
> Institut of Inorganic and Analytical Chemistry
> Johannes Gutenberg - University
> 55099 Mainz
> and
> Max Planck Institute for Chemical Physics of Solids
> 01187 Dresden
> ________________________________________
> Von: Wien [wien-bounces at zeus.theochem.tuwien.ac.at<mailto:wien-bounces at zeus.theochem.tuwien.ac.at>] im Auftrag von karima Physique [physique.karima at gmail.com<mailto:physique.karima at gmail.com>]
> Gesendet: Samstag, 6. Mai 2017 01:50
> An: A Mailing list for WIEN2k users
> Betreff: [Wien] paramagnetic or diamagnetic
>
> Dear Wien2k users:
>
> How I can know if the material is paramagnetic or diamagnetic with a calculation.?
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