[Wien] Discrepancy in the simulation of the paramagnetic state

[E.A.Moore]

In the paramagnetic state, as Prof. Blaha says, the atoms still have magnetic moments but they are randomly oriented. This arises when the thermal energy is sufficient to overcome the spin-spin coupling. I would expect a calculation on Gd at 0K to give you a ferromagnetic state with very small spin-spin coupling. You can check the coupling by a run with one spin reversed.


I am not convinced you can model a paramagnetic state with a DFT calculation and zero moments is not a good model. Your second example reads as though it is reporting experimental results on the magnetisation and does not seem to provide a model for calculations.


I would also agree with Prof. Blaha about the factors influencing efg. Interatomic distance is very important in calculating this.

Elaine A. Moore
The Open University
UK

________________________________
From: Wien <wien-bounces at zeus.theochem.tuwien.ac.at> on behalf of Abderrahmane Reggad <jazairdz at gmail.com>
Sent: 26 November 2016 21:30
To: wien at zeus.theochem.tuwien.ac.at
Subject: Re: [Wien] Discrepancy in the simulation of the paramagnetic state


Thank you Prof Blaha for your quick answer.

The Ni atom is 3d transition metal . But my question is about the simulation of the paramagnetic state. There are many people that considere that the paramagnetic state is the non-spin polarierd one and the magnetic moment is zero, but you say no and the magnetic moments exist in arbitrary directions and my quoting is about that.

I have given 2 examples for that discrepancy with your statement.

Best regards
--
Mr: A.Reggad
Laboratoire de Génie Physique
Université Ibn Khaldoun - Tiaret
Algerie


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