Re: AMBER: missing impropers for nitros?

From: David A. Case <>
Date: Sat, 12 May 2007 10:37:27 -0700

On Fri, May 11, 2007, David Mobley wrote:
> I'm running ANTECHAMBER and LEAP to try and generate GAFF parameters
> for a variety of small molecules, and I keep getting warnings about
> missing improper torsions for pretty much everything with a nitro
> group (for example, 1-nitrobutane gives me a warning about "No sp2
> improper torsion term for c3-o-no-o".

I think you already know this, but just in case: these are just informational
messages. There is no requirement that every possible improper be included.

That said, Junmei can probably comment on whether this is intentional or an
oversight. If the former, we might put a "zeroed" out entry in gaff.dat to
suppress the warning message.


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Received on Sun May 13 2007 - 06:07:48 PDT
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