Structural, optical, mechanical, dielectric and nonlinear optical studies of rubidium hydrogen oxalate dihydrate (RbC4H7O10) single crystal

A transparent Rubidium hydrogen oxalate dihydrate (RbHOH) single crystal was synthesized by adopting the slow solvent evaporation method. RbHOH crystallizes in the triclinic structure with the P1‾ space group. The characteristic FTIR spectrum reflects the vibrational modes of water molecules and hydroxyl groups available in the material. From the absorption spectrum, the lower cutoff wavelength of RbHOH was at 260 nm with an energy gap of 4.74 eV. From TG/DSC, the thermal stability of RbHOH is around 91 °C. The normal indentation size effect of the material was verified with the help of Vickers microhardness analysis.Dielectric measurement has been performed over a wide range of temperature, as a function of frequencies. The third-order nonlinear susceptibility of RbHOH was calculated as 3.95242 × 10−6 esu.