Practical Electron Microscopy and Database

An Online Book, Second Edition by Dr. Yougui Liao (2006)

Practical Electron Microscopy and Database - An Online Book

Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix

R-3m (166) Space Group

Table 3007. R-3m (166) space group.

Name in the International Tables for Crystallography
R-3m R
166 -3m
Crystal system
Trigonal -3m
36 Example of forbidden reflections in electron diffraction patterns {1 -1 0 0} reflections
Asymm
0 ≤ x ≤ 2/3 and 0 ≤ y ≤ 2/3 and 0 ≤ z ≤ 1/6 and x ≤ 2 y and y ≤ min(1-x,2 x)
Symmetry (atomic coordinates)
X, Y, Z; -Y, X-Y, Z; Y-X, -X, Z; Y, X, -Z; X-Y, -Y, -Z; -X, Y-X, -Z; -X, -Y, -Z; Y, Y-X, -Z; X-Y, X, -Z; -Y, -X, Z; Y-X, Y, Z; X, X-Y, Z; 2/3+X, 1/3+Y, 1/3+Z; 2/3-Y, 1/3+X-Y, 1/3+Z; 2/3+Y-X, 1/3-X, 1/3+Z; 2/3+Y, 1/3+X, 1/3-Z; 2/3+X-Y, 1/3-Y, 1/3-Z; 2/3-X, 1/3+Y-X, 1/3-Z; 2/3-X, 1/3-Y, 1/3-Z; 2/3+Y, 1/3+Y-X, 1/3-Z; 2/3+X-Y, 1/3+X, 1/3-Z; 2/3-Y, 1/3-X, 1/3+Z; 2/3+Y-X, 1/3+Y, 1/3+Z; 2/3+X, 1/3+X-Y, 1/3+Z; 1/3+X, 2/3+Y, 2/3+Z; 1/3-Y, 2/3+X-Y, 2/3+Z; 1/3+Y-X, 2/3-X, 2/3+Z; 1/3+Y, 2/3+X, 2/3-Z; 1/3+X-Y, 2/3-Y, 2/3-Z; 1/3-X, 2/3+Y-X, 2/3-Z; 1/3-X, 2/3-Y, 2/3-Z; 1/3+Y, 2/3+Y-X, 2/3-Z; 1/3X-Y, 2/3+X, 2/3-Z; 1/3-Y, 2/3-X, 2/3+Z; 1/3+Y-X, 2/3+Y, 2/3+Z; 1/3+X, 2/3+X-Y, 2/3+Z
Crystal examples
K3H(SeO4)2: Parelastic & paraelectric.
Rb3H(SeO4)2: Parelastic.