Hi, All Phenix Users,

I am fitting 2-bromoethanol to the density map. I want to keep its gauche conformation, so I edited the cif for this ligand to restrain the torsion angle,

loop_
_chem_comp_tor.comp_id
_chem_comp_tor.id
_chem_comp_tor.atom_id_1
_chem_comp_tor.atom_id_2
_chem_comp_tor.atom_id_3
_chem_comp_tor.atom_id_4
_chem_comp_tor.value_angle
_chem_comp_tor.value_angle_esd
_chem_comp_tor.period
BRJ Var_01        BR1      CB      CB1     OB1         -60.00  0.0 3


But, after refinement, this angle can be close to 90 or even 120. Even worse is that the fitting at such angles are not better than at -60/60 angle.

How could I fix/restrain the angle during refinement?

Thanks!

Charles

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Charles Chen

Research Associate

University of Pittsburgh School of Medicine

Department of Anesthesiology

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