Trouble opening CFour output

Juanes · September 14, 2026, 4:57pm

I’m trying to open some CFour optimizations to test the new Z-matrix functionality but they fail to do so with the error"

with "OpenBabel: Generic Output file format" failed.
OpenBabel error: conversion failed.

I’d appreciate any guidance.

Opt_CO.out (76.2 KB)

ghutchis · September 14, 2026, 5:10pm

Does Open Babel support CFour output? I don’t think cclib does either.

It’s probably easier to add CFour support via Python - either as a separate Avogadro plugin or better as a patch to cclib. I’d certainly support it in Open Babel, but I’d point the parser towards cclib first.

ghutchis · September 14, 2026, 5:19pm

And incidentally, I don’t think we have a CFour input generator either

Juanes · September 14, 2026, 6:36pm

Going back to the contributions, if I find the time at some point soon, I’d be happy to help getting at least some basic CFour support via either cclib or OpenBabel. Let me know.

ghutchis · September 14, 2026, 6:51pm

I looked and there’s at least some older ACES output support:

github.com/openbabel/openbabel

src/formats/acesformat.cpp

9be528bcd

/**********************************************************************
Copyright (C) 2011 by Michael Banck

Based on nwchemformat.cpp,
Copyright (C) 2001-2006 by Geoffrey R. Hutchison
Some portions Copyright (C) 2004 by Chris Morley
Some portions Copyright (C) 2009 by Michael Banck

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.
***********************************************************************/
#include <openbabel/babelconfig.h>

#include <openbabel/obmolecformat.h>

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erb74 · September 21, 2026, 5:03pm

If you use cclib 1.9rc1 it should work. Sorry there isn’t a final tag yet but this is basically it barring any crazy blockers appearing.

ghutchis · September 21, 2026, 7:33pm

I’ll double-check that I get a notification for releases, but I can bump the cclib plugin at that point to require the new version.