obrotamer - Man Page

generate conformer/rotamer coordinates

Synopsis

obrotamerfilename

Description

The obrotamer tool can be used as part of a conformational search by generating random isomers based on rotating dihedral angles. These rotamers are not conformers — that is, obrotamer does not perform geometry optimization after generating the rotamer structure. The obminimize tool can do geometry optimization using molecular mechanics.

Environment

OB_RANDOM_SEED

Seed for pseudo random number generator; random seed is used if unset or null. This feature is effective if Open Babel is built with -DOB_USE_OBRANDOMMT cpreprocessor flag (will be automatically enabled when version 4 is released).

Examples

obrotamer baseconformer.sdf > rotamer1.sdf

Generate a random rotational isomer of baseconformer.sdf and write it to rotamer1.sdf

See Also

obabel(1), obenergy(1), obfit(1), obgrep(1), obminimize(1), obrotate(1).

The web pages for Open Babel can be found at: <https://openbabel.org/>

Authors

Open Babel is developed by a cast of many, including current maintainers Geoff Hutchison, Chris Morley, Michael Banck, and innumerable others who have contributed fixes and additions. For more contributors to Open Babel, see <https://openbabel.org/docs/Introduction/thanks.html>

Referenced By

obabel(1), obenergy(1), obminimize(1).

May 26, 2026