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

摘要

In this study, we investigated the structural dynamic features of the [NH_(3)(CH_(2))_(2)NH_(3)]ZnCl_(4) crystal as a function of temperature through magic angle spinning (MAS) ~(1)H nuclear magnetic resonance (NMR), MAS ~(13)C NMR, and static ~(14)N NMR. From the chemical shifts, changes in the structural environments of ~(13)C and ~(14)N were evident. The ~(1)H spin–lattice relaxation time (T _(1ρ)) values at high temperatures undergo molecular motion according to the Bloembergen–Purcell–Pound theory, and the ~(13)C 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 ~(1)H and ~(13)C obtained from T _(1ρ) are discussed. In addition, we compare the structural dynamics of diammonium-type [NH_(3)(CH_(2))_(2)NH_(3)]ZnCl_(4) obtained in this study and monoammonium-type [CH_(3)NH_(3)]_(2)ZnCl_(4) previously reported. The findings reported herein can provide important insights for potential applications of [NH_(3)(CH_(2))_(2)NH_(3)]ZnCl_(4) crystals.