Computational design and molecular modeling of the interaction of nicotinic acid hydrazide nickel-based complexes with H2S gas

Abstract

The application of nickel complexes of nicotinic acid hydrazide ligand as a potential gas-sensor and adsorbent material for H₂S gas was examined using appropriate density functional theory (DFT) calculations with the ωB97XD/Gen/6-311++G(d,p)/LanL2DZ method. The FT-IR spectrum of the synthesized ligand exhibited a medium band at 3178 cm⁻¹ attributed to ν(NH) stretching vibrations and strong bands at 1657 and 1600 cm⁻¹ corresponding to the presence of ν(CO) and ν(CN) vibration modes. In the spectrum of the nickel(II) complex, the ν(CO) and ν(CN) vibration bands experience negative shifts to 1605 cm⁻¹ and 1580 cm⁻¹, respectively, compared to the ligand. This indicates the coordination of the carbonyl oxygen and the azomethine nitrogen atoms to the Ni²⁺ ion. Thus, the sensing mechanism of the complexes indicated a short recovery time and that the work function value increases for all complexes, necessitating an excellent H₂S gas sensor material. Thus, a profound assertion was given that the complex sensor surfaces exhibited very dense stability with regards to their relevant binding energies corresponding to various existing studies.