Chemical Adsorption Of Acrylonitrile On Transition Metal Copper Surface & La And Mn Complexes: A Density Functional Study

In this paper, the adsorption of acrylonitrile (AN) on the different sites of Cu (100), (110) and (111) surface has been studied theoretically by means of cluster model with density functional theory (DFT). The main investigative results are as follows: AN adsorbs perpendicularly to the surface and bonds to the metal sites via a nitrogen-metal interaction took a weak chemisorption. Such chemisorption leds to electron transfer between AN molecule and copper cluster. In the metal complexes of Cucluster-AN, theσ-binding via the lone-pair electrons on the N atom is observed. Chemisorption on the top site of Cu(100) and (110) are preferred with their adsorption energies of 40.74 and 17.82 kJ?mol-1 and the equilibrium N-surface distances of 0.2279 and 0.21268 nm respectively. It is more stable for AN adsorbed on the bridge site of Cu(111) with the adsorption energy of 40.16 kJ?mol-1 and N-surface distance of 0.1191 nm. After adsorption, the backbone bonds of AN changed a lot, which can be indicated by the variety of bond lengths, bond angles, bond orders, IR spectroscopy and hybridization of chemical bonds. When AN is adsorbed on Cu(100) and (111), the major contributions to the entropy decrease came from rotations and contributions of AN, since these motions were decreased upon Chemisorption. NBO analysis explained these structural changes, and activity of AN by the chemisorption.Density functional theory was also used to fully optimize the building blocks of La(III) complex with Schiff-base [LaL¹(NO₃)]NO₃·5H₂O (L1:(CH₃)₂CHCH₂CH(N CHC₄H_3^- -O) COO-) and Mn(II) coordination complex with 8-hydroxy-quinoline (8-OHQ)₃-Mn. The optimized results are shown as follows: In La complex, one N atom and three O atoms of ligand L¹ and two O atoms of nitric ion coordinate with La(III) ion, forming a 6-coordinated asymmetric compound. The average bond length of La?N is 0.2637 nm and of La?O is 0.2526 nm. In Mn complex, one N atom and O atom of 8-hydroxy-quinoline coordinate with Mn(II) in a bidentate chelating mode, forming a 6-coordinated asymmetric...