OBROTAMER(1)

📦
version 3.2.1 · 3 versions
, in arch rolling, opensuse-leap 16.0

💅 OBROTAMER(1) — like, the obrotamer tool, bestie

okay so welcome to the obrotamer page from the Open Babel User's Reference Manual — she's giving niche-but-iconic and honestly? we're obsessed 🎀

✨ NAME ✨

obrotamer — generate conformer/rotamer coordinates 🌀

🦋 SYNOPSIS 🦋

obrotamer filename

that's it. that's the whole vibe. one filename, no drama, periodt ✨

🌸 DESCRIPTION 🌸

so here's the tea ☕ — the obrotamer tool is something you can use as part of a conformational search, and what it does is generate random isomers based on rotating dihedral angles. like, it just spins stuff around and hands you a new structure, iykyk 🔄

but — and this is the important part, bestie, don't skip it — these rotamers are not conformers. that is, obrotamer does not perform geometry optimization after generating the rotamer structure. it literally just rotates and dips 💀 no glow-up, no refinement, nothing.

if you do want geometry optimization, the obminimize tool can do that using molecular mechanics. so like, go talk to her instead 🫶

🌈 ENVIRONMENT 🌈

  • OB_RANDOM_SEED — the seed for the pseudo random number generator 🔢. if it's unset or null, a random seed is used. heads up though: this feature is effective if Open Babel is built with the -DOB_USE_OBRANDOMMT cpreprocessor flag (and it'll be automatically enabled when version 4 is released). so like, it's cute but it's conditional 💅

🔥 EXAMPLES 🔥

obrotamer baseconformer.sdf > rotamer1.sdf

this generates a random rotational isomer of baseconformer.sdf and writes it to rotamer1.sdf — slay, so simple 💖

🧚 SEE ALSO 🧚

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> 🫶 main character energy from the whole crew, honestly.

Copyright (C) 1998-2001 by OpenEye Scientific Software, Inc. Some portions Copyright (C) 2001-2007 by Geoffrey R. Hutchison and other contributors.

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.

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.

ngl the all-caps warranty disclaimer is giving serious "read the terms and conditions" energy but fr fr it matters — no warranty, bestie, none 😭

and that's the page!! brought to you by Open Babel 3.2, dated May 26, 2026 — mwah, love u, go make some rotamers 💅💖✨

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