The quantum and computational investigation of adsorption of glycine on the surface of C12Si12 nanocluster in pristine and N, B doped states.

The aim of this study is to determine the best absorption state of the pristine and (N, B) doped C12Si12 nanocluster as a sensor to detect, and adsorb glycine molecule, by studying the effect of glycine amino acid adsorbing on the structural and electrical properties of C12Si12 nanocluster in the pristine and doped states. For this purpose, 18 adsorbing states have been selected and all calculations for all considered configurations were performed by using function theory density (DFT) at the level of B3LYP/6-31G(d, p) and Gaussian 09 software. Also by using optimized structures, HOMO and LUMO structures, parameters NMR, NBO and Muliken charge plots, electrostatic potential prodecures (MEP) and thermodynamic parameters, diagram DOS and IR, UV parameters, RDG structures, quantum theory of atoms in the molecule QIM, AIM values and solubility effect and Quantum parameters have been calculated. Results obtained from the bond length between glycine and C12Si12 nanocluster and the energies of Eads and Ebin and the free energy of Gibbs show that in general in all states adsorbing of pristine nanostructurales and glycine, adsorption, is favorable and occurs spontaneously and in the case of doped states, only in the absorption position b (D-b, E-b, F-b) means the absorption position on the oxygen side attached to the single glycine bond to the nanostructure doped, is favorable. The results of electrostatic potential (MEP) and Mulicen charge and natural bonding of NBO, HOMO and LUMO show the amino acid glycine has an electron donating effect and the most negative charge is around the absorption position and surface of glycine and the most positive charge is located around the surface of the nanostructure. All this results showed that the nanocluster C12Si12 and (B and N) doped are a good choices to use as sensors to detect the amino acid glycine.