Investigation of the structure, phase transitions, molecular dynamics, and ferroelasticity of organic-inorganic hybrid NH(CH(3))(3)CdCl(3) crystals.

Understanding the physical and chemical properties of the organic-inorganic hybrid NH(CH(3))(3)CdCl(3) is essential for its application. Considering its importance, a single crystal of NH(CH(3))(3)CdCl(3) was grown with an orthorhombic structure at 300 K. The phase transition temperatures were determined to be 345 (T(C3)), 376 (T(C2)), and 452 K (T(C1)) (phases IV, III, II, and I, respectively, starting from a low temperature). The partial decomposition temperature was 522 K (T(d)). Furthermore, the NMR chemical shifts of the (1)H, (13)C, and (113)Cd atoms of the cation and anion varied with increasing temperature. Consequently, a significant change in the coordination geometry of Cl around Cd in CdCl(6) and a change in the coordination geometry of H in NH was associated with changes in the N-H⋯Cl hydrogen bond near the phase transition temperature. The (13)C activation energy E(a) obtained from the spin-lattice relaxation time was smaller than that of (1)H E(a), suggesting that energy transfer around (13)C is easier. Additionally, a comparison of the twin domain walls measured via optical polarizing microscopy and Sapriel's theory indicated that the crystal structure in phase III was more likely to be orthorhombic than hexagonal.