AMBER Archive (2004)

Subject: AMBER: gaff: hydrogen atom types

From: astrid.maass (
Date: Tue Mar 30 2004 - 01:37:58 CST

Dear amber team,

by applying the latest antechamber version (thanks to Julien Michel for
the makefile!), I noticed that hydrogen atoms attached to carbon in e.g.
formaldehyde or formamide get the ha atom type (hydrogen attached to
aromatic carbon). However, following the documentation (Development and
Testing of a General Amber Force Field, Wang et al.) I would expect the
atom types h4 and h5 (hydrogen attached to aromatic carbon with 1/2
electron withdrawing goups). Am I right? To which kind of functional
group would these atom types correspond else?

Best wishes and thanks in advance,


Dr. Astrid Maass
Fraunhofer-Institute for 
Algorithms and Scientific Computing (SCAI)
Schloss Birlinghoven
D-53754 Sankt Augustin, Germany

Phone: +49 - 2241 - 14 - 2481 Fax: +49 - 2241 - 14 - 2181 E-mail: Internet: ==========================================

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