The C 2 H 10 N 2 Cl NCS (EDCT) compound is characterized by using infrared spectroscopy. The infrared spectrum of the title compound was recorded (400-4000 cm −1) at room temperature and discussed, essentially in terms of vibrational modes of [C 2 H 10 N 2 ] 2+ cations and [SCN] − and [Cl] − anions. Ethylenediammonium thiocyanate chloride crystallizes, at room temperature, in the triclinic system, space group P1 (C i). The entities [C 2 H 10 N 2 ] 2+ , [SCN] − and [Cl] − occupy sites of symmetry (C 1). Several ground state thermodynamic parameters were calculated using the ab initio Hartree-Fock (HF) and DFT (B3LYP) methods with 6-31++G (d, p) and 6-311++G (d, p) basic sets such as vibration frequencies, rotation constants, and optimized molecular geometry. The comparison between the theoretical and experimental infrared spectrum showed good agreement.