[Wien] EFG Tensors in Wien

[Peter Blaha]

> (A) What type of transformation is used to go from the spherical
> representation to the middle-left tensor.
> 
> I do understand that the following takes us from spherical to the tensor:
> 
> V22-V20/SqRt(3)    V22M                            V21
> V22M                        -V22-V20/SqRt(3)        V21M
> V21                            V21M                            2*V20/SqRt(3)
> 
> I don't quite see where this came from, nor do I see what space this will
> transform into (it isn't second rank irreducible tensor representation, is
> it?).

Write the potential as multipole expansion   (sum_LM V_lm Y_lm)
now form the EFG, which is the tensor of 2nd derivatives.
Than for example Vzz is obviously connected with Y_20, because Y_20
is proportional to z^2 and this term does NOT vanish when you differentiate,
while others do.


> (B) There is a second column after the spherical representation, the "SRF"
> column.  I don't quite understand what this is (also, what does SRF stand
> for?).

SRF stands for "surface". The way we calculate the V_lm coefficients is
by an integral over the sphere (usually the main contribution) plus a
surface integral (containing the boundary value problem and the fourier-
coeff. of rho.


                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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