Tcl dihedral restraints in CG minimisation

From: Ben Roberts (
Date: Tue Nov 02 2004 - 17:01:28 CST

Hi all,

Recently I have been trying to use Tcl dihedral restraints during a
minimisation to force amides to go trans.

This seems to badly break the conjugate gradients algorithm, whether
"addenergy" is turned on or off. The energy, even, seems to maximise
rather than minimise.

Does anyone have any idea why this should be the case?

Attached is my Tcl script (restraints.tcl) for your information.

Thanks in advance, and best regards,


Benjamin P. Roberts, B.Sc.(Hons)
Ph.D. Student

Department of Medicinal Chemistry
Victorian College of Pharmacy (Monash University)
381 Royal Parade, Parkville VIC 3052, Australia

Phone +61 3 9903 9674 | Fax +61 3 9903 9582 | Mobile +61 401 784 940

This archive was generated by hypermail 2.1.6 : Wed Feb 29 2012 - 15:37:57 CST