[Pw_forum] (no subject)

Paolo Giannozzi giannozz at democritos.it
Sun Aug 3 21:52:54 CEST 2008

On Sunday 03 August 2008 04:27, Padmaja Patnaik wrote:

> I have doubt in calculating magnetic moment.  Found few communications
> on this topic but no where a clear answer is found. If i want to find out
> the magnetic moment of an atom in a system, how am i going to get it.

a clear answer has been given many times on this forum: there is no
such thing as "the magnetic moment of an atom in a system". You can
define such a quantity by using appropriate projections onto atomic or
atomic-like wavefunctions or partition of the charge into domains, but
the results will depend upon the choice of the procedure

> Lowdin Charges:
>       Atom #   5: total charge =   4.5686, s, p, d, f =   0.2749   0.8321  
>       spin up       =   2.9945, s, p, d, f =   0.1449   0.4269  2.4227 
>       spin  down  =   1.5742, s, p, d, f =   0.1300   0.4052  1.0390
>       polarization =   1.4203, s, p, d, f =   0.0149   0.0217  1.3837
> How do i get the magnetic moment for the atom 5 from this? 

hint: polarization = spin up - spin down. Of course if you are looking
for orbital contributions as well things are much more complicated

Paolo Giannozzi, Democritos and Udine University

More information about the users mailing list