From chemistry-request@ccl.net Thu May 16 09:03:48 1991
Date:         Thu, 16 May 91 20:18:55 SST
From: Chin W S <RP83115%NUSVM.BITNET@OHSTVMA.ACS.OHIO-STATE.EDU>
Subject:      Gaussian 86 6-31G eigenvalues
To: CHEMISTRY@ccl.net
Status: R

Hi,

I am using the default 6-31G basis sets in the program GAUSSIAN 86.
I found that under the section EIGENVALUES of output file, Hydrogen
atom is having 1S and 2S component, Carbon atom has 1S,2S,2P as well
as 3S and 3P, while atoms like Sulfur has up to 4S and 4P but no 4D
component. Can anyone tell me whether these are actually corresponding
to the contracted (inner ) and diffuse ( outer ) functions calculated
using 6-31G split-valence basis sets ?

Thanks in advance,

Wee Shong

From chemistry-request@ccl.net Thu May 16 16:42:46 1991
Date: 16 May 91   15:53 LCL
From: PA13808%UTKVM1.BITNET@OHSTVMA.ACS.OHIO-STATE.EDU
To: CHEMISTRY@ccl.net
Subject: BITNET mail follows
Status: R

Topic G86 SPLIT VALENCE EIGENVALUES
   The request on this topic does not make much sense to me.the a 6-31G s
set for carbon has no 3s or 3p component etc it only has an inner
sp component and an outer sp component. To see what basis set you have yo
should insert the request GFPRINT.Also see Poples book or one of the rece
recent reviews by D. FELLER and E.S. DAVIDSON especially the one in
REVIEWS IN COMPUTATIONAL CHEMISTRY ED BY K.B. LIPKOWITZ AND D. B. BOYD
published by VCH. Possibly  Mr Chin is using an unconventional terminolog
y for the principsl quantum number. To get ds into S one has to use a*
and then you will only get a ds for a 3d shell. to put in higher ones
you have to use the MASSAGE OPTION OR put in a new basis from scratch
using GEN option.Remember when using Gaussians one does not specify the p
prin. quantum number and one identifies the shell by the eigenvalue
and by relating it to the atomic shell. Perhaps you are misinterpreting
this relationship. To clarify run some atomic calc. on G 86 with your
basis and compare them with standard tables of atomic energy values.
   John E. Bloor (PA13808 at UTKVM1 on CMS)


From chemistry-request@ccl.net Thu May 16 21:10:19 1991
Date: Thu, 16 May 91 19:29 CST
From: "JORGE M. SEMINARIO" <JSMCM@canal.crc.uno.edu>
Subject: Re: Gaussian 86 6-31G eigenvalues
To: RP83115%NUSVM.BITNET@ohstvma.acs.ohio-state.edu, chemistry@ccl.net
Status: R

Regarding the 6-31G basis in G86:
The 2S and 3S are the inner and outer functions used to
give more flexibility to the 2S character of the first row atoms.
In the same way if you use 6-311G, you will get 2S, 3S, and 4S for
the triple split 2S character of the same atoms.
The numbers are used to facilitate bookeeping.
Hope this help
Jorge M. Seminario