Subject: CCL:G:Convention for the d orbitals in G94

From: Steve Williams <[email-masked]>
Date: Tue, 07 Oct 1997 09:52:42 -0400

Dear CCLers,

Is there anybody who could give me the matching between the labeling
that Gaussian 94 uses to describe the LCAO coefficents of the d orbitals
and the classical description of d orbitals (dZ2,dXY,DX2-Y2,...). 
I put below the labeling i got into the output of G94.

D 0         ->
D+1         ->
D-1         ->
D+2         ->
D-2         ->

Geoffrey

The notation that G94 uses is the standard notation for the spherical
harmonics; these are the angular parts of the atomic wavefunctions obtained
by solving the schrodinger equation forthe H atom.  These are complex
functions.  It is possible to construct an equivalent set of functions that
are real valued from these, and it is this set of commonly used real valued
functions that you refer to.

The real functions are linear combinations of the complex valued ones.
Except for normalizations and possible multiplications by i, the
connections that you want are:
D0 = dz^2
D+1  +  D-1  = dxz
D+1  -  D-1  = dyz
D+2  +  D-2  = dx^2-y^2
D+2  -  D-2  = dxy

Hope this helps,
Steve

*****************************************
Steve Williams               F    F    F
Chemistry                     \  / \  /
Appalachian State University   Al   Al
Boone, NC 28608               /  \ /  \
USA                          F    F    F
[email-masked]