Subject: field-gradients calculation

From: "Dr. Jose S. DUCA" <[email-masked]>
Date: Thu, 22 May 1997 18:16:55 -0500

Dear CCLers;
I need to calculate the field-gradient near a carbon-halogen bond (say,
for instance neutral chlorobencene) and I would like to know if there
exists any _subroutine_, _program_ or whatever that allows me to do so.
The first idea is to use an equation of the type (based on any
wavefunction, I mean, semiempirical or ab initio one)

q(el)=SUM_p(INT[PSI_m <Hq> PSI*_m]), with
Hq=(3 cos^2(theta_kp)-1)/(r_kp^3)

see: Nuclear Quadrupole Coupling Constants, E.A.C. Lucken, pp. 100

where SUM_p is a summatory over pth elements, INT is the integral over
the whole space, PSI is the wavefunction, and Hq the mentioned
field-gradient operator.

I could write the code, but I really want to know if I could earn the
time...
Any comments are welcome,

Jose

-- 
Dr. Jose Santiago Duca, Jr.
PhD. in Chemical Sciences

Computational Chemistry and Electron Transfer Group
A.P. 4, C.C. 61  	Voice: 54-51-334170 Fax: 54-51-333030
(5016) Cordoba		Dept. of Organic Chemistry
National University of Cordoba - ARGENTINA