Crystal structure, High-resolution X-ray diffraction and Hirshfeld surface analysis of a novel third-order nonlinear optical crystal: Diisopropylammonium oxalate

Abstract

To quench the escalated demand of the photonic industry, substantial research has been focused on the development of new nonlinear optical materials. In the present work, we report the growth of novel Diisopropylammonium oxalate crystal, a potential candidate for third-order nonlinear optical properties. The titled crystal was subjected to a number of characterization methods to evaluate its structure and properties. The single crystal X-ray diffraction was employed to calculate the lattice parameters as a = 7.9151 Å, b = 9.7957 Å, c = 14.3528 Å, α=γ=90°, β= 103.851° The crystal belongs to the monoclinic space group P21/n. The high resolution X-ray diffraction demonstrates the crystalline quality, presence of dislocations, defects, grain boundaries, etc. of the grown single crystal. The 3D Hirshfeld surface analysis was utilized to illustrate the molecular interactions present inside the single crystal of Dipa-O. HOMO-LUMO analysis and MEP studies have been carried out at the DFT/B3LYP/6–311G(d, p) level of theory. Whereas, 1H and 13C Nuclear Magnetic Resonance studies were carried out on the crystal to discover the bonding and chemical environment within its molecule. For the assessment of optical properties, UV–Vis and Photoluminescence studies were conducted. The thermal analysis of the material was done through Thermal gravimetric/Differential thermal analysis studies which show that the crystal is stable up to 155 °C. The third harmonic generation behavior of the titled crystal was confirmed by Z-scan analysis. The nonlinear absorption coefficient is calculated as 4.10 × 10−12 cm/W and nonlinear refractive index as -1.11 × 10−17 cm2/W.