num_symm_settings: Number of space group settings

In cry: Statistics for Structural Crystallography

Number of space group settings

Description

Although a space group is uniquely defined, i.e. the symmetry operations defining it is 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. While 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

num_symm_settings(SG = NULL)

Arguments

SG	A character string or a number indicating the space group.

Value

nsett The number of setting for the given space group.

Examples

# P 1 21 1 (group number 4) has three settings
num_symm_settings(4)

# Find the extended Hermann-Mauguin symbols
translate_SG(4,"number","xHM",1)$msg
translate_SG(4,"number","xHM",2)$msg
translate_SG(4,"number","xHM",3)$msg

cry documentation built on Oct. 10, 2022, 9:06 a.m.