Restrained molecular dynamics simulations were performed to study the binding affinity of the peptide with alkanethiols of different tail-groups, S（CH2）7CH3, S（CH2）7OH and S（CH2）7COOH, which self-assembled on Au...Restrained molecular dynamics simulations were performed to study the binding affinity of the peptide with alkanethiols of different tail-groups, S（CH2）7CH3, S（CH2）7OH and S（CH2）7COOH, which self-assembled on Au（111） surface in the presence of water molecules. The curves of binding affinity were calculated by fixing the center of mass of the peptide at various distances from the assembling surface. Simulation results show that the binding affin- ity is in the order as COOH-SAMs〉OH-SAMs〉CH3-SAMs, while 100% COOH-SAMs〉5% COOH-SAMS in concentration. The effects on binding affinity by different tail-groups were also studied. Results show that the binding affinity between COOH-SAMs and the peptide is bigger than those of the others and increasing the acidity of COOH-SAMs will result in stronger attractive power.展开更多
The B3LYP/LanL1MB and B3LYP/LanL2DZ methods for Ag atom in conjunction with the 6-31G（d） basis set for S, C and H atoms were used to optimize the geometries and calculate the energies for （SCH3）mAg20 （re=1-4）, r...The B3LYP/LanL1MB and B3LYP/LanL2DZ methods for Ag atom in conjunction with the 6-31G（d） basis set for S, C and H atoms were used to optimize the geometries and calculate the energies for （SCH3）mAg20 （re=1-4）, respectively. A single molecular adsorption energy of （SCH3）m （rn=1-4） on Ag20 and the intermolecular substrate-mediated interaction energy were evaluated. The results revealed that there is a proportional relation between the single molecular adsorption energy and the substrate-mediated intermolecular interaction energy. The results qualitatively demonstrated the semi-empirical expression for the substratemediated interaction energy proposed previously by us is consistent with the results of the density functional theory.展开更多
文摘Restrained molecular dynamics simulations were performed to study the binding affinity of the peptide with alkanethiols of different tail-groups, S（CH2）7CH3, S（CH2）7OH and S（CH2）7COOH, which self-assembled on Au（111） surface in the presence of water molecules. The curves of binding affinity were calculated by fixing the center of mass of the peptide at various distances from the assembling surface. Simulation results show that the binding affin- ity is in the order as COOH-SAMs〉OH-SAMs〉CH3-SAMs, while 100% COOH-SAMs〉5% COOH-SAMS in concentration. The effects on binding affinity by different tail-groups were also studied. Results show that the binding affinity between COOH-SAMs and the peptide is bigger than those of the others and increasing the acidity of COOH-SAMs will result in stronger attractive power.
基金Ⅴ. ACKN0WLEDGMENTSThis work was supported by the National Natural Science Foundation of China （No.20473078） and The Ph.D. Programs Foundation of Ministry of Education of China （No.20020358061）.
文摘The B3LYP/LanL1MB and B3LYP/LanL2DZ methods for Ag atom in conjunction with the 6-31G（d） basis set for S, C and H atoms were used to optimize the geometries and calculate the energies for （SCH3）mAg20 （re=1-4）, respectively. A single molecular adsorption energy of （SCH3）m （rn=1-4） on Ag20 and the intermolecular substrate-mediated interaction energy were evaluated. The results revealed that there is a proportional relation between the single molecular adsorption energy and the substrate-mediated intermolecular interaction energy. The results qualitatively demonstrated the semi-empirical expression for the substratemediated interaction energy proposed previously by us is consistent with the results of the density functional theory.
