To cite this article: Thangaraj, U. D. et al. (2017). Synthesis, crystal structure and vibrational spectral analysis of guanidinium hydrogen L-aspartate single crystal. J. Phys. Sci., 28(1), 27-47, https://doi.org/10.21315/jps2017.28.1.3To link to this article: https://doi.org/10.21315/jps2017.28.1.3 ABSTRACT: Single crystals of guanidinium hydrogen L-aspartate (GULAS), a salt of guanidine derivative, have been grown by slow-cooling method and characterised by infrared (IR) spectroscopy, powder and single-crystal x-ray powder diffraction (XRD). From the vibrational spectral analysis, the spectral band assignment is carried out to identify the various functional groups in GULAS.After arriving at the equilibrium geometry, the analysis of intramolecular charge transfer interactions using natural bond orbital (NBO) method, first order hyperpolarisability, molecular electrostatic potential and frontier molecular orbitals have been carried out using density functional theory. The second-order NLO response is also studied using Kurtz and Perry powder method.