Crystal Chemistry Midterm Flashcards Pt1

I am manifesting a B+ in this class

Triclinic

V = abc (1 - cos²α – cos²β – cos²γ + 2 cos α cos β cos γ)^1/2 ; 1, 1bar

Monoclinic

V = abc sin β, Cos2 β + sin2 β = 1; Includes: Simple, End-Centered; 2, m, 2/m

Orthorhombic

V = abc, cos90=0; Includes: Simple, Body-Centered, Face-Centered, End Centered; mm2, 222, mmm

Tetragonal

V = a²c cos90=0; Includes: Simple, Body Centered; 4, 4bar, 4/m, 4mm, 4/mmm 4bar2barm

Hexagonal

V = a²c*(3/4)^1/2, cos²120 = 1/4; 6, 6bar, 6/m, 622, 6mm, 6barm2, 6/mmm

Trigonal/Rhombohedral

V = a³(1-3cos²α+2cos³α)^1/2, cos α = cos β = cos γ; 3, 3bar, 3m, 3bar, 32

Cubic

V = a³, cos 90 = 0; Includes: Simple, Face Centered, Body Centered; 23, m3, 4bar3barm, 43, m3m

m

Mirror plane parallel to X & Z, Perpendicular to Y

1/m

Mirror plane perpendicular to Z , Parallel to Y and X

1bar

Inversion Center

nfold Rotation

4mm

4/m

Vertical Mirror (m, 2mm, 3m, 4mm, 6mm)

6bar

3⟂m

4/m

rotation and reflection

Polar point groups

1, 2, m, mm2, 4, 4mm, 3, 3m, 6, 6mm

Monoclinic symmetry elements

2 : 2 parallel Z2

m : m perpendicular Z2

2/m : 2 parallel Z2, m perpendicular Z2

Orthorhombic symmetry elements

Trigonal symmetry elements

Tetragonal symmetry elemts

Hexagonal Symmetry Elements

Cubic Symmetry Elements