Systematic investigation and comparison of oxalic acid dihydrate, ammonium oxalate hydrate and ammonium hydrogen oxalate oxalic acid dihydrate single crystals

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Vol. 288; p. 116157
• Main Authors: Mahendra, K., Fernandes, Brian Jeevan, Pattar, Jayadev, Pujar, Swati, Nagaraja, B.S., Ramesh, K.P., Udayashankar, N.K.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2023
• Subjects: Ammonium hydrogen oxalate oxalic acid dihydrate; Ammonium oxalate hydrate; Dielectric; Oxalic acid dihydrate; Single crystal; Dielectric; Ammonium oxalate hydrate; Ammonium hydrogen oxalate oxalic acid dihydrate; Single crystal; Oxalic acid dihydrate
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2022.116157

•Single crystals of OAD, AOH, and AHOOD were grown using a slow evaporation method.•SCXRD studies of OAD, AHO, and AHOOD revealed monoclinic, orthorhombic and triclinic crystal systems respectively.•The bandgap energies of AHO, OAD, and AHOOD crystals were found to be 4.27 eV, 4.05 eV, and 4.02 eV respectively.•The photoluminescence studies exhibit emission peaks at 305 nm, 321 nm and 362 nm for AHO, OAD, and AHOOD crystals.•Impedance spectroscopy analysis reveals AHOOD crystals are highly conductive (AC), when compared to that of AHO crystals. Semiorganic crystals are hybrid materials that have captured the interest of researchers due to their improved material characteristics and applications. In the current work, single crystals of oxalic acid dihydrate (OAD), Ammonium oxalate hydrate (AHO), and Ammonium hydrogen oxalate oxalic acid dihydrate (AHOOD) were grown using a slow evaporation method. Single crystal and powder XRD measurements were carried out to elucidate their unit cell parameters, crystal system, and structural information. To comprehend the interplay of light and matter, optical investigations like UV–Vis Spectroscopy and photoluminescence studies were performed. Interaction of ammonium with oxalic acid, and thus formed crystals, was investigated using impedance spectroscopy. Detailed dielectric parameters such as dielectric constant, dielectric loss, impedance, conductivity, and electric modulus were explored as a function of frequency. Vickers hardness test was used to calculate the hardness, Meyer's number, brittleness, and fracture toughness. The crystals were determined to be of the hard materials group.