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2.3 Basic structure types

CdCl -type
2

Crystal data

Formula sum CdCl 2
Crystal system trigonal

Space group R -3 m (no. 166)

Unit cell dimensions a = 6.2300 Å, = 36°
Z 1

Atomic coordinates Stacking sequence

Atom Ox. Wyck. x y z

Cd1 +2 3a 0 0 0
Cl1 -1 36i 0.25(1) 0.25(1) 0.25(1) One layer

Structural features:tructural features:
S
• layered structure, sequence (Cl-layers): ABC

• Cd is coordinated octahedrally by 6 Cl (via six common edges)

• polytypes