Table 4.

Chiral and polar axes of the Sohncke groups. c is assumed to be a unique axis for the monoclinic system. The rhombohedral axes are assumed for trigonal systems (e.g., 32), for hexagonal setting Laue class 321 must be distinguished from 312. Single axes are denoted by [], groups of axes are denoted by <>.

Crystal System	Laue Class	Point Group	Chiral Axes	Polar Axes
Monoclinic	2	$C_2$	[001]	[001]
Orthorhombic	222	$D_2$	[001], [100], [010]	None
Tetragonal	4	$C_4$	[001]	[001]
	422	$D_4$	[001], [100], [010],	None
			[110], [$\overline{1}10$]
Trigonal	3	$C_3$	[001]	[001]
	32	$D_3$	[111], [$1\overline{1}0$],	[$1\overline{1}0$],
			[$01\overline{1}$], [$\overline{1}01$]	[$01\overline{1}$], [$\overline{1}01$]
Hexagonal	6	$C_6$	[001]	[001]
	622	$D_6$	[001], [100], [010],	None
			[$\overline{1}10$], [$\overline{1}\overline{1}0$],
			[210], [120]
Cubic	23	T	$〈111〉$, $〈100〉$	$〈111〉$
	432	O	$〈111〉$, $〈100〉$, $〈110〉$	None