The temperature-dependent photoluminescence, dielectric and impedance spectra, as well as crystal structures have been investigated for the iodoplumbate-based hybrid crystal, [C3-Apy][PbI3] (1) (C3-Apy+ = 1-propyl-4-aminopyridinium). Compound 1 in the room temperature (RT) contains [PbI3]∞ chains formed by face-sharing distorted PbI6 octahedral. In the low-temperature (LT) phase, the disordered propyl groups in HT phase are partly ordered. 1 shows novel dielectric relaxation and thermochromic luminescent properties.
