[Wien] spin distribution in organic

[Yue Hai]

Dear sir:
    I have a larger organic system (36 inequivalent atoms per unit cell ) 
and want to study the magntic character of it. The experiment has shown 
that there is about 1.0 μB/mol for the  magnet moment. From the spin 
polarization calculation , I found that the  magnet moment of one molecule 
is  1.00μB, which is in agreement with the experiment. But there is a 
larger spin population in the interstitial region. For example: the sum of 
spin populations on all atoms is about 0.58μB/mol, while the spin 
population in the interstitial region is about 0.42μB/mol.   I don not 
know if this is correct or possible. 
   I want to know the reason of it :
     1: if this is because of the samll MT sphere  or other inappropriate 
parameters used in the  calulation?. 
     2: or it is due to the fact that there is no localized spin center in 
the organic material  because of the hyperconjugation effect,while the 
calculated spin populatoin on the atom is confined in the MT sphere,  so 
the spin population in the interstitial region  is larger?
     3: I want to know the spin distribution in the molecule space. If 2 is 
correct, is it  appropriate to  plot the spin electron density  (the spin 
up electrons minus spin down  electron) to represent the spin distribution 
in the molecule? 

 The parameters I used in the calculation : 
   The RMT for H is 0.6,  and the RMTs for O, C, N are  1.1-1.2
   RKmax=2.5 , Gmax=20 and 10 k-points in the IBZ

   It wil be very grateful If some can help me or give me  advice about it 
.


Best wishes

Hai

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