X-Ray Study of Low Temperature Phases in {N(CH3)4}2ZnCl4

The superstructures are found in low temperature phases of {N(CH 3 ) 4 } 2 ZnCl 4 . With decreasing temperature, the cell dimension of the pseudo-hexagonal axis changes as c 0 , ∼5 c 0 , 5 c 0 , 3 c 0 , c 0 and 3 c 0 , where c 0 is the fundamental repeated unit of the structure. The space groups of each phases are P m c n ( Z =4), incommensurate, P 2 1 c n ( Z =20), P 112 1 / n ( Z =12), P 12 1 / c 1( Z =4) and P 2 1 2 1 2 1 ( Z =12), respectively.