Synthesis, structural, topographical, linear and nonlinear optical, electrical and mechanical properties of Bisthiourea zinc acetate single crystal

•PXRD confirms the grown BTZA crystal is crystalline in nature.•The PL spectrum shows a prominent emission in the blue region.•Refractive index was determined experimentally and found to be 1.508.•AFM analysis reveals that the crystal has flat and smooth surface.•High Elastic stiffness constant indicates strong binding forces between ions.

Nonlinear optical material Bisthiourea Zinc Acetate (BTZA) was synthesized by slow evaporation solution growth technique. The grown crystals were characterised by Single crystal XRD and powder XRD studies. The presence of functional groups and the co-ordination of metal ions to Thiourea were confirmed by FTIR analysis. The UV-vis –NIR spectrum shows a low absorption in the entire visible and IR region. Optical band gap of the grown crystal was found to be 4.18 eV. The photoluminescence studies carried out and the crystal has blue emission. The Refractive Index was determined experimentally for the first time and found to be 1.508 for the incident wavelength of 632.8 nm. The second harmonic generation efficiency was determined using Kurtz and Perry powder technique and it was 0.7 times than that of the KDP crystal. Thermal properties were studied by thermo gravimetric analysis and differential thermal analysis. Dielectric studies were carried out at different frequencies for various temperatures. The mechanical behaviour of the grown crystal was studied using Vickers micro hardness tester. The growth mechanism and surface features are investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM).