Subject: Specifying specific isotopes with LANL2DZ or other ECP basissets

From: eric breynaert <eric.breynaert!at!agr.kuleuven.ac.be>
Date: Tue, 10 Aug 2004 19:45:41 +0200

Hello all,

I'm  doing some dft calculations on 99Tc compounds in Gaussian 03 using 
UB3LYP/LANL2DZ.
I was wondering how one deals with different isotopes when using an ECP 
basisset. Browsing through the gaussian logfile i found that g03 uses 
atomic weigths 12.0000000, 15.9949146 and 1.0078250 for C,O and H 
respectively. while it uses .0000000 for Tc. Is it possible to specify the 
atomic weight for the Tc isotope i'm trying to model, and would this have 
an effect on the calculations ?

Thanks,

Eric

---------
*  Eric Breynaert
*  Labo voor Colloodchemie
*  Departement Interfasechemie
*  K.U.Leuven
*  Kasteelpark Arenberg 23
*  B-3001 Leuven
*  BELGIUM
*
*  Tel: +3216321457
*  Fax: +3216321998
---------