TORSION_SCALAR

This is part of the colvar module

Calculate a torsional angle.

Examples

Glossary of keywords and components

The atoms involved can be specified using

ATOMS

the four atoms involved in the torsional angle

Or alternatively by using

AXIS	two atoms that define an axis. You can use this to find the angle in the plane perpendicular to the axis between the vectors specified using the VECTORA and VECTORB keywords.
VECTORA	two atoms that define a vector. You can use this in combination with VECTOR2 and AXIS
VECTORB	two atoms that define a vector. You can use this in combination with VECTOR1 and AXIS

Or alternatively by using

VECTOR1	two atoms that define a vector. You can use this in combination with VECTOR2 and AXIS
VECTOR2	two atoms that define a vector. You can use this in combination with VECTOR1 and AXIS

Options

NUMERICAL_DERIVATIVES	( default=off ) calculate the derivatives for these quantities numerically
NOPBC	( default=off ) ignore the periodic boundary conditions when calculating distances
COSINE	( default=off ) calculate cosine instead of dihedral