Pentanedioic acid-thiourea (PAT), a new hydrogen-bonded organic co-crystal, was produced using a slow evaporation method and examined for its structural and solid-state properties. Single-crystal X‑ray diffraction confirmed an orthorhombic Pnma structure, stabilized by N–H···O and O–H···S hydrogen-bonding frameworks. The FTIR spectrum validated the functional groups and successful co-crystallization. Optical absorption analysis revealed a strong UV band at 232 nm, a sharp cutoff at 298 nm, and a wide bandgap of 4.165 eV, showing UV-filtering and semiconducting properties. The low Urbach energy (0.085 eV) indicated that the material was well-crystallized and had fewer defects. Dielectric tests revealed temperature and frequency-dependent behavior, with AC conductivity following a thermally activated hopping process. Thermal investigation revealed a multi-stage decomposition process, with stability up to 126°C. Thus, the remarkable solid-state properties of PAT co-crystal make it a suitable material for optoelectronic and UV-filtering uses.
Albert et al. (Sun,) studied this question.