Subject: Combining different basis sets

From: "Moshe Olshansky" <[email-masked]>
Date: Tue, 14 Nov 95 15:52:09 IST

Dear CCL'ers!
We are working on computational aspects of the Hartree-Fock procedure.
For this purpose we would like to have some f-type basis functions
but not too many of them,  while all the basis sets we have either
do not have f functions at all or have too many of them (our trial
molecule contains H C N and O atoms).
Since we are not chemists I would like to ask the following
(possibly very trivial) question:  does it make any sense to combine
two different basis sets (for example,  take a smaller basis set for
H and C and a larger one - containing d and f functions - for N and O)?

Thank you very much and please forgive my ignorance
Moshe Olshansky
IBM Israel Science and Technology
<[email-masked]>