[Wien] About the magnetic moment of vanadium in vanadium sulphide

[E.A.Moore]

Your calculations are probably fine.

Apologies for my previous posting but my point was partly that I think you said the  experimentalists claimed it was Pauli paramagnetic.

Pauli paramagnetism is not the type of paramagnetism that arises from unpaired electrons on metal ions in, for example, transition metal complexes. It is a property of metals. It arises if there is an unfilled conduction band. In an external magnetic field, one type of spin (up or down) acquires a different energy to the other type resulting in an excess of one type over the other and hence paramagnetism.

Both your result and the nonmagnetic finding are consistent with the existence of Pauli paramagnetism.

You results suggest that the 3 unpaired electrons on V are not localised on V but are in a delocalised band. Do you predict VS has a partially full conduction band?

Elaine A. Moore

From: Wien [mailto:wien-bounces at zeus.theochem.tuwien.ac.at] On Behalf Of Abderrahmane Reggad
Sent: 07 September 2017 16:11
To: wien at zeus.theochem.tuwien.ac.at
Subject: Re: [Wien] About the magnetic moment of vanadium in vanadium sulphide

Hi All

I have used the PBE+EECC calculation for 3 configurations: nm, fm and afm I and I found that the afm I is the most stable.

The energy criterion and charge are 0.001 Ry and 0.001 e respectively.

I don't worry about if the material is really antiferromagnetic or paramagnetic because of:

1- I found only one experimental study that they found the compound to be pauli magnetic and one theoritical study which they found the compound to be non magnetic and these two studies are not sufficient to judge the compound to be in a such state. The theoritical study used the GGA method which is not good for correlated systems.

2- In the anfiferromagnetic state afm I in the NiAs structure for vanadium sulphide I found the following results:

MMI for V1: 0.05 MB
MMI for V2 :- 0.05 MB
MMI for S:    0 MB

My questions are now:

what's the definition of non magnetic compound ?

I think we can talk about non magnetic calculation and not about non magnetic compounds.

As Blaha said we can't silulate the paramagnetic state or at at least it's difficult to do it because we can't orientate the spins randomly ang maintain the total magnetic moment equals to zero.

Because of the Hind's prediction and because the impaired number of the V2+ ion to equal 3 I believe the atomic magnetic moment to be different from zero.

Best regards
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