The Crystal Structure of (CH₃)₃NHCdCl₃ in the Orthorhombic (2×\sqrt3) Phase

Abstract

The structure of a linear chain compound (CH₃)₃NHCdCl₃ was investigated at 355 K using a four-circle diffractometer. The structure belongs to the orthorhombic system, space group Pbnm. Unit cell dimensions are a=17.123 A, b=15.256 A, c=6.731 A and Z=8. The structure was refined by a block-diagonal least squares method. The obtained result in general agrees with the model reported previously. The disorder state of the trimethyl ammonium ions with unequal occupation propabilities is discussed. The mechanism of the phase transition from the room temperature (1×\sqrt3) phase to the high temperature (2×\sqrt3) phase is also discussed.