Growth and characterizations of pure and co doped piperazinium L-tartrate single crystals (PPLT) single crystals: Optical and NLO properties

Single crystal of pure and cobalt (Co) doped piperazinium l-tartrate (PPLT) was grown by slow evaporation solution growth method. The effects of Co-doping on the growth, structural, optical, dielectric and NLO properties of PPLT crystals have been investigated. Powder XRD results demonstrate that both pure and Co doped PPLT crystals have crystal belongs to monoclinic system with non-centrosymmetric space group P21. The PPLT crystal has a large transmission window with a low near-UV cut-off wavelength of 231 nm, according to a UV-vis-NIR study. The incorporated Co ion could significantly improve the optical, mechanical, dielectric, conductivity and activation energy of PPLT crystal. The etching experiments were carried out to determine the crystal development pattern. The addition of Co to PPLT crystals improves optical transmittance, energy band gap, second and third order nonlinear optical efficiency, as well as the laser damage threshold. Density functional theory computations of equilibrium geometry and the first order hyperpolarizability of the crystal were calculated. The optimized geometric bond lengths and bond angles obtained by using DFT (B3LYP/6-31G (d,p)) show good agreement with the experimental data.