find_symm_setting {cry}

Find specific space group setting

Description

Although a space group is uniquely defined, i.e. the symmetry operations defining it are uniquely given, the choice of vectors that defines a unit cell for that symmetry is not unique. The different choices are known as settings. Most space groups have only one setting, but it is possible to find space groups with several settings. For example, "C 1 2/c 1" has 18 settings. The xHM symbol for setting 1 is "C 1 2/c 1", the symbol for setting 2 is "A 1 2/n 1", etc.

Usage

find_symm_setting(SG)

Arguments

SG

A character string indicating the extended Hermann-Mauguin symbol for the space group.

Value

set An integer equal to the specific setting corresponding to the given xHM symbol.

Examples

# P2 (group number 4) has three settings
nsets <- find_symm_setting("P 1 2 1")
print(nsets)