cry (version 0.5.2)

syminfo_to_op_xyz_list: Operators of a specific space group

Description

Returns human-readable symmetry operators corresponding to a specific input space group.

Usage

syminfo_to_op_xyz_list(SG)

Value

op_xyz_list A named list made of two vectors. The first vector, SYMOP, contains strings describing the symmetry operators. The second vector, CENOP, contains strings describing the centring of the unit cell.

Arguments

SG

A character string. The extended Hermann-Mauguin symbol (e.g. 'P 1 1 21')

Details

A crystallographic space group includes a set of symmetry operators that can be expressed like operations on the (x,y,z) fractional coordinates of atoms in a unit cell. So, for example, The only operator associated with the space group P 1 is "x,y,z", while the four operators associated with P 21 21 21 are "symop x,y,z", "symop -x+1/2,-y,z+1/2", "symop x+1/2,-y+1/2,-z", "symop -x,y+1/2,-z+1/2".

Examples

# Symmetry operators for space group number 3, P 1 2 1
SG <- "P 1 2 1"
ltmp <- syminfo_to_op_xyz_list(SG)
ltmp