AMBER Archive (2005)

Subject: AMBER: restraint only for Z cartegian coordinate?

From: Jaroslav Hanus (
Date: Tue Feb 22 2005 - 09:40:58 CST

I would like to know, whether there is a way to restrain the motion of
some atoms only in one of its cartegian coordinates, for example to
restrain only the z component and leave the x an y free (to keep some
atoms in a predefined plane). From the manual it seemed to me that in
principle it can be possible, but I did not find a way how to do this.
Manual for Amber 8, page 101:
RESTRAINT_WT: The weight (inkcal/mol−Å 2)for the positional
restraints. The restraint is of the formk(∆x) 2, where k is the value
given by this variable, and∆x is the difference between one of the
Cartesian coordinates of a restrained atom and its reference position.
There is a term like this for each Cartesian coordinate of each
restrainted atom.
thanks, sincerely


Jaroslav Hanus
Centre de Recherches sur les Macromolécules Végétales
BP 53 38041 Grenoble Cedex 9 France

Tel 33 (0)4 76 03 76 49
Fax 33 (0)4 76 54 72 03

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