fixing dihedrals in structure optimization

Total energy, geometry optimization, DFT+U, spin....

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elena.mol
Posts: 17
Joined: Wed Apr 21, 2010 1:05 pm

fixing dihedrals in structure optimization

Post by elena.mol » Fri Dec 20, 2013 4:14 pm

Dear all,
is it possible in Abinit to fix dihedral angles, instead of fixing single atoms (iatfix etc.), in a structure optimization run? At the moment i'm still using version 7.0.5, but of course i can upgrade to a more recent version, if this functionality has appeared in the meantime. Note that my system is an aminoacid, not a crystal, therefore no symmetry, no periodicity etc, and coordinates are in xcart form.

I'm doing calculations on aminoacids, and i need to fix some dihedrals (in order to choose a particular rotamer, or conformation), while performing structure optimization on all the rest of the molecule to relax bond lengths and some angles.


Best season's greetings, and thanks a lot in advance
Elena Molteni
Department of Physics
Universita' degli Studi di Milano
via Celoria, 16
I-20133, Milan, Italy
and European Theoretical Spectroscopy Facility (ETSF)
http://www.etsf.eu

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