Trigonal and rhombohedral space groups

4 Trigonal and rhombohedral space groups (1) Space group P3 (no. 147), multiplicity = 6 

The crystal structure of the salt [ K(2.2.2-crypt) 2][Pt Pbi2] contains a dianion composed of a cage of 12 Pb atoms that encloses a centered Pt atom, denoted 

Crystal structure of Ca[Be2N2l the Be, N and Ca atoms are represented by circles of increasing size. From E. N. Esenturk, J. Fettinger, F. Lam and B. Eichhorn, Angew. Chem. Int. Ed. 43, 2132-4 (2004). 

Crystalline. s-triazine undergoes a phase transition from a rhombohedral structure (space group R3c) at room temperature to a monoclinic structure (space group C2/c) below 198 K. 

Crystal structure of a-rhombohedral boron (a) a layer of linked Bj2 icosahedra viewed along the c axis (b) linkage between layers. 

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