Re: RESP charges

From: Lepsa <>
Date: Tue 9 Oct 2001 09:56:49 +0200

Dear Eva,
AFAIK you mingled the inputs for the 1st and 2nd stages of RESP. The 1st
should be: iqopt = 1 (charges reset to zero), qwt = 0.0005 (softer fitting
restraint than for the 2nd stage), and default nmol = 1 and ihfree =1. The
2nd stage should have values iqopt = 2 (reads in charges from the 1st stage
using '-q resp1.qout' option in the resp executing command line), qwt =
0.001, and the above two defaults (needn't be written in). As for the 2nd
column of numbers, in the 1st stage you put zeros only and in the 2nd stage
you put -99 to all heavy atoms and non-methyl,non-methylene hydrogens. For
methyl- and methylene-hydrogens (only those and maybe some other nonpolar
groups but not for amine hydrogens, for example) you put 0 to the first
hydrogen and the order number of the above hydrogen to the others.

E.g. methyl
line atom weight ivary
33 6 -99
34 1 0
35 1 34
36 1 34

I suppose you put 0 to C atoms, haven't you? Try the above procedure, it
should work.

Best regards,

   Martin Lepsik
Received on Tue Oct 09 2001 - 00:56:49 PDT
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