Operators of a specific space group

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

Usage

syminfo_to_op_xyz_list(SG)

Arguments

SG

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

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.

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
#> $SYMOP
#> [1] "x,y,z"   "-x,y,-z"
#> 
#> $CENOP
#> [1] "x,y,z"
#>