On Tue, 18 Dec 2001, Alessandro Bagno wrote:
> (1) When I calculate the shieldings of highly symmetric molecules, the
> values of symmetry-equivalent nuclei are sometimes rather different even
> though a single-point calculation perceived the correct symmetry. This
> holds particularly for the paramagnetic component. Any hint?

If you have symmetry-equivalent nuclei, -and- SCF converges to a
fully symmetric solution, with reasonably tight convergence
criteria (say 10**-5 or better), -and- calculated isotropic
shieldings and/or principal components differ by more than
about 10**-(ACCINT-1) fraction of the largest contribution,
you have something strange going on. Try posting a complete
example (including run script, all inputs, and the complete
program output) - and somebody might be able to help you.

Regards,

Serguei

---
Dr. Serguei Patchkovskii
Tel: +1-(613)-991-2719
Fax: +1-(613)-947-2838
E-mail: Serguei.Patchkovskii_at_nrc.ca
Research Council Officer
Theory and Computation Group
Steacie Institute for Molecular Sciences
National Research Council Canada
Room 2158, 100 Sussex Drive
Ottawa, Ontario
K1A 0R6 Canada