.Dd May 26, 2026
.Dt OBROTAMER 1 URM
.Os "Open Babel" 3.2
.Sh NAME
.Nm obrotamer
.Nd "generate conformer/rotamer coordinates"
.Sh SYNOPSIS
.Nm
.Ar filename
.Sh DESCRIPTION
The
.Nm
tool can be used as part of a conformational search
by generating random isomers based on rotating dihedral angles.
These rotamers are not conformers \(em that is,
.Nm
does not perform geometry optimization after generating the rotamer
structure.
The obminimize tool can do geometry optimization using molecular mechanics.
.Sh ENVIRONMENT
.Bl -tag -width flag
.It Ev 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 \fI-DOB_USE_OBRANDOMMT\fP
cpreprocessor flag (will be automatically enabled when version 4 is released).
.El
.Sh EXAMPLES
.Dl "obrotamer baseconformer.sdf > rotamer1.sdf"
.Pp
Generate a random rotational isomer of baseconformer.sdf and write
it to rotamer1.sdf
.Sh SEE ALSO
.Xr obabel 1 ,
.Xr obenergy 1 ,
.Xr obfit 1 ,
.Xr obgrep 1 ,
.Xr obminimize 1 ,
.Xr obrotate 1 .
.Pp
The web pages for Open Babel can be found at:
\%<\fBhttps://openbabel.org/\fR>
.Sh AUTHORS
.An -nosplit
Open Babel is developed by a cast of many, including current maintainers
.An Geoff Hutchison ,
.An Chris Morley ,
.An Michael Banck ,
and innumerable others who have contributed fixes and additions.
For more contributors to Open Babel, see
\%<\fBhttps://openbabel.org/docs/Introduction/thanks.html\fR>
.Sh COPYRIGHT
Copyright (C) 1998\-2001 by OpenEye Scientific Software, Inc.
.br
Some portions Copyright (C) 2001\-2007 by Geoffrey R. Hutchison and
other contributors.
.Pp
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation version 2 of the License.
.Pp
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.