3.60 Symmetry, Structure and Tensor Properties of Materials
DISTRIBUTION OF LATTICE TYPES, POINT GROUPS AND PLANE GROUPS AMONG THE TWO-DIMENSIONAL CRYSTAL SYSTEMS
SYSTEM (4) LATTICE (5) POINT GROUP (10) PLANE GROUPS (17)
OBLIQUE PRIMITIVE Preallelogram (oblique) 1 P1
a ≠ b 2 P2
γ GENL
RECTANGULAR PRIMITIVE Rectangle m Pm
a ≠ b Pg
γ = 90° CM
CENTERED RECTANGLE 2mm P2mm
(DHAMOND) P2mg
P2gg
C2mm
SQUARE SQUARE 4 P4
a = b
γ = 90° 4mm P4mm
P4gm
HEXAGONAL HEXAGONAL (EQUILATERAL) 3 P3
a₁ = a₂
γ = 120° 3m P3m1
P31m
6 P6
6mm P6mm