The title molecular salt, (E)-2-(1-phenylethylidene) hydrazinecarboximidamide nitrate hemimethanol (C9H13N4+center dot NO3-center dot 0.5CH(4)O), was synthesized and characterized by elemental analysis, FT-IR and NMT spectroscopies, and single-crystal X-ray diffraction technique. Quantum chemical calculations were performed to study the molecular and spectroscopic properties of the title compound, and the results were compared with the experimental findings. The calculated results show that the optimized geometry can well reproduce the crystal structure parameters, and the theoretical vibrational frequencies and GIAO H-1 and C-13 NMR chemical shifts show good agreement with experimental values. The dipole moment, linear polarizability and first hyperpolarizability values were also computed. The linear polarizabilities and first hyper polarizabilities of the studied molecule indicate that the compound is a good candidate of nonlinear optical materials. On the basis of the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between standard heat capacities (C) standard entropies (S), and standard enthalpy changes (H) and temperatures. (C) 2013 Elsevier B.V. All rights reserved.