[Wien] QTL for 3d elements

[Jorissen Kevin]

The chemical valence of an element is only a *very* rough approximation of the charge on the atom ...  So you should not expect to lose a charge of 4 e when going to valency +4.  Changes in the charge density tend to be much smaller than that.
Furthermore, the output in case.scf(2) that you quote below integrates only the charge in the muffin tin, which is an entirely technical, unphysical concept.  So there is no reason why the charge in the MT should equal the charge of the atom (and that, too, is not really a strictly defined quantity ...).  Eg. Bader analysis tends to show unspherical atomic bassins.
 
As for the partial d-charges ...  I'd try to visualize the charge density in xcrysden if it is not obvious from the structure, hope that helps.
 
Good luck,
 
Kevin.
 

________________________________

Van: wien-admin at zeus.theochem.tuwien.ac.at namens M.Y.Wu
Verzonden: ma 20-9-2004 17:28
Aan: wien-zeus.theochem.tuwien.ac.at
Onderwerp: [Wien] QTL for 3d elements



Dear Wien2k users,

I tried CaMnO3 (Pnma space group, 4  NONEQUIV.ATOMS), I don't understand
the QTL value I got for Mn, is there someone can help me?
the results I got is following:
:CHA002: TOTAL CHARGE INSIDE SPHERE   2 =    12.293294
:PCS002: PARTIAL CHARGES SPHERE =  2
S,P,D,F,PX,PY,PZ,D-Z2,D-X2Y2,D-XY,D-XZ,D-YZ
:QTL002: 2.0928 6.0158 4.1542 0.0260 2.0050 2.0057 2.0050 0.8994 0.6955
0.9663 0.6087 0.9842
         Q-s-low E-s-low   Q-p-low E-p-low   Q-d-low E-d-low   Q-f-low E-f-low
:EPL002:  2.0031 -5.3019    5.8797 -3.0432    0.0608 -0.7636    0.0037 -0.7695
         Q-s-hi  E-s-hi    Q-p-hi  E-p-hi    Q-d-hi  E-d-hi    Q-f-hi  E-f-hi
:EPH002:  0.0897  0.1214    0.1360  0.2095    4.0934  0.3595    0.0222  0.3267

My question is: why the partial charges on D-XZ is smaller than D-XY and
D-YZ, and D-Z2 is larger than D-X2Y2?
                         why the total partial charges on 3d is 4.1542. I
think it should be 3 or a little larger as Mn is 4+ in CaMnO3.

Best regards,
Mengyue

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