Evaluation of vanadium coordination compounds derived from simple acetic acid hydrazide as non-conventional semiconductors

Vanadium hydrazone complexes were prepared by the reaction of [VO(C5H7O2)2] and NH4VO3 with hydrazone ligands. The ligands were prepared by the reaction of acetic acid hydrazide with 2-hydroxy-5-nitrobenzaldehyde (H2L1), 2-hydroxybenzaldehyde (H2L2), or 2-hydroxy-3-methoxybenzaldehyde (H2L3). Mononuclear and dinuclear vanadium(v) complexes were characterized by spectroscopic methods and elemental analysis, while their thermal behaviour was examined by thermogravimetry and temperature-dependent powder X-ray diffraction. The structural transformations of specific complexes were observed by applying the in situ solid-state impedance spectroscopy (SS-IS) technique, and their electrical characteristics were systematically correlated with their thermal and structural properties. Crystal and molecular structures of complexes (NH4)[VO2(L1)], [VO(L1)(OMe)(MeOH)], [VO(L2)(OMe)(MeOH)]center dot MeOH, [VO(L3)(OMe)(MeOH)], [VO(L3)(OEt)(H2O)], and [VO2(HL3)]2 center dot 2H2O, were determined by single crystal X-ray diffraction and their optical properties were assessed using UV-Vis diffuse reflectance spectroscopy. Vanadium(v) complexes prepared from acyl-hydrazones were obtained. The structural transformations were observed by applying in situ impedance spectroscopy, while electrical characteristics were correlated with thermal and structural properties.