Re: AMBER: impose: Illegal angle internal definition

From: David A. Case <>
Date: Wed, 29 Sep 2004 12:13:36 -0700

On Wed, Sep 29, 2004, Madalin Giambasu wrote:
> I want modify an angle value using xleap:
> impose gf {1 } { { C2 C3 C4 04 -117 } }
> I receive the following message:
> impose: Illegal angle internal definition

The immediate problem is that you wrote "zero-four" for the oxygen atom
name, rather than "capital O-four". LEaP's parser knows that there is
an error, but is not very smart about localizing it for you.

However, the "impose" command also cannot handle changing torsions inside a
ring system. If you want to change the pucker of the ring, you may have to
play around some with the order in which you enter the atoms; or find a
smarter program -- this command is really designed for open-chain systems, not
for ring systems. (I know it doesn't say that in the manual....)

....good luck...dac

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Received on Wed Sep 29 2004 - 20:53:01 PDT
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