A computational study of N₂ adsorption on aromatic metal Mg₁₆M;(M=Be, Mg, and Ca) nanoclusters

Metal nanoclusters have been considered as a new class of chemical sensors due to their unique electronic structures and the particular physicochemical properties. The interaction of N₂ molecule with neutral and ionic magnesium nanoclusters Mg₁₇^q(q=0,±1), as well as neutral magnesium nanoclusters with the centrality of beryllium and calcium Mg₁₆M (M=Be, Mg, and Ca) have been investigated using CAM-B3LYP/6-311+G(d) level of theory in the gas phase. The electronic properties of magnesium nanoclusters were significantly affected by the adsorption of N₂ molecule. The NBO analysis revealed a charge transfer from the adsorbed N₂ molecule to the nanocluster. Based on the adsorption energies and enthalpies, a thermodynamically favorable chemisorption process was predicted for the Mg₁₆Ca-N₂ complex. The negative value of the Gibbs free energy of Mg₁₆Ca-N₂ confirmed the spontaneous adsorption process. The estimated recovery time for Mg₁₆Ca-N₂ complex for 8-MR (0.089 s) and 4-MRs (0.075 s) illustrated a possible desorption process for N₂ molecule from the surface of Mg₁₆Ca. Our finding also revealed the Mg₁₆Ca has the ability to use as a sensor for detection and absorption of N₂ molecule.