Single crystals of the organic–inorganic hybrid compound [N(C3H7)4]2Cd2Cl6 were synthesized by an aqueous solution method, and their structural and dynamic properties were systematically investigated. Thermal analyses revealed phase transitions at 321 K (TC1) and 445 K (TC2), followed by melting at 476 K. Single-crystal X-ray diffraction indicated that the compound crystallizes in a triclinic system with space group P \(\:\stackrel{-}{1}\) , showing variations in lattice parameters across TC1 while maintaining the same symmetry. On the other hand, whereas the 1H, 13C, and 14N MAS NMR chemical shifts of the [N(C3H7)4] cations showed little variation near TC1, the 113Cd MAS NMR spectra of the Cd2Cl6 anions revealed a clear change, with two Cd sites (Cd(1) and Cd(2)) merging into a single site. This agrees well with the SCXRD results, indicating that the phase transition at TC1 arises primarily from an order–disorder transition of the Cd2Cl6 anions rather than the [N(C3H7)4] cations. In addition, temperature-dependent line narrowing in the1H, 13C, 14N, and 113Cd NMR spectra reflects enhanced molecular dynamics at elevated temperatures. These results provide insights into the phase behavior and stability of [N(C3H7)4]2Cd2Cl6, highlighting its potential relevance for future functional applications.
