Thermodynamic Properties, Structural Characteristics, and Cation Dynamics of Perovskite-Type Layer Crystal [NH3(CH2)2NH3]ZnCl4

In this study, we investigated the structural dynamic features of the [NH3(CH2)2NH3]­ZnCl4 crystal as a function of temperature through magic angle spinning (MAS) 1H nuclear magnetic resonance (NMR), MAS 13C NMR, and static 14N NMR. From the chemical shifts, changes in the structural environments of 13C and 14N were evident. The 1H spin–lattice relaxation time (T 1ρ) values at high temperatures undergo molecular motion according to the Bloembergen–Purcell–Pound theory, and the 13C T 1ρ value also varied abruptly with increasing temperature. Although the phase-transition temperature was not detected from the differential scanning calorimetry result, the chemical shifts and T 1ρ results showed discontinuities around 300 K. Herein, the activation energies of molecular motion for 1H and 13C obtained from T 1ρ are discussed. In addition, we compare the structural dynamics of diammonium-type [NH3(CH2)2NH3]­ZnCl4 obtained in this study and monoammonium-type [CH3NH3]2ZnCl4 previously reported. The findings reported herein can provide important insights for potential applications of [NH3(CH2)2NH3]­ZnCl4 crystals.