Subject: MOPAC: unreasonable structures

From: Frank Herrmann <[email-masked]>
Date: Mon, 3 Oct 1994 01:26:33 +0100

Dear netters,

when doing single point calculations (1SCF) on molecule conformations
containing clashes ( non bonded distance ~= 1A ) the following
problems occur:

1- either MOPAC do not terminate even when using T=...
2- or the energy is far below that of resonable structures

MOPAC checks if the bond distance is < 0.8A. But the clashes should at
least, if not resulting in an error, raise the energy. Is this a bug
or is there an explanation ?

Regards,

--------------------------------------------------
Frank Herrmann, Dept. of Molecular Biophysics 0810
German Cancer Research Center
Im Neuenheimer Feld 280, D-69120 Heidelberg
Tel: (49) 6221-422336, FAX: (49) 6221-422333
email: [email-masked]