[Wien] need clarification on changes in spin magnetic moment in cell after SCF run

[Fecher, Gerhard]

How well are youre charges converged ? (see e.g. in the dayfile)
In "Force optimization" the charge convergence is most probably better then in youre regular calculation?
Did you use -cc = 0.0001 or something like that.

A moment of -0.00168 uB is essentially Zero.
Are youre MMI in the same order ?

Different signs of individual moments have principally nothing to do with non-colinear magnetic order.

Why do you use spinpolarized calculations when you already know that the material does not show any magnetic order ?



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
________________________________________
Von: wien-bounces at zeus.theochem.tuwien.ac.at [wien-bounces at zeus.theochem.tuwien.ac.at]" im Auftrag von "venkatesh chandragiri [venkyphysicsiitm at gmail.com]
Gesendet: Freitag, 16. August 2013 13:20
An: wien at zeus.theochem.tuwien.ac.at
Betreff: Re: [Wien] need clarification on changes in spin magnetic moment in cell after SCF run

Dear sir,


I am very thankful for your prompt reply. I have few comments on your reply as given below




"If the total magnetic moment appears/disappears during geometry optimization, it means that you are close to a non-magnetic/magnetic phase transition."



Yes sir, my structure has to be non-magnetic one.




"It can happen that a functional does not give the correct magnetic phase."


Sir, i have used same functional (PBE-GGA) for the both force optimization and scf run. In Force optimization, i have got MMTOT = 0 uB, but in scf case with optimized structure gives -0.00168 uB. Why this happens even i took same functional form.

"The sign of :MMTOT has no physical meaning. What is important is to compare the signs of the magnetic moments in the spheres (:MMI00)."


Sir, i have seen MMI of all spheres in the given structure. It is observed that some of the random spheres have negative moments with different amplitudes and the others have positive magnetic moments of different amplitudes. what sort of magnetic nature this indicates...? can we call it as a Non-co-linear magnetic structure..?





Thanking you and looking forward to your comments sir,



regards,


Ch. Venkatesh,

C/o. Prof. V. Srinivas,
Department of Physics & Meteorology,
IIT Kharagpur.
ph: +919445909693