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2.3 Basic structure types

CdI -type
2

Crystal data
Formula sum CdI 2

Crystal system trigonal

Space group P -3 m 1 (no. 164)

Unit cell dimensions a = 4.2500 Å, c = 6.8500 Å
Z 1

Atomic coordinates

Atom Ox. Wyck. x y z Stacking sequence

Cd1 +2 1a 0 0 0
I1 -1 2d 1/3 2/3 1/4

Structural features:tructural features:
S
• layered structure, sequence (I-layers): AB

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

• polytypes