First-principles study of interaction of cluster Au_(32) with CO,H_2,and O_2

摘要

First-principles calculations are performed to study the interaction of cluster Au_(32) with small molecules,such as CO,H_2,and O_2.The cagelike Au_(32)(I_h) shows a higher chemical inertness than the amorphous Au_(32)(C_1) with respect to the interaction with small molecules CO,H_2,and O_2.H_2 can only be physically adsorbed on Au_(32)(I_h),while it can be dissociatively chemisorbed on Au_(32)(C_1).Although CO can be chemically adsorbed on Au_(32)(I_h) and Au_(32)(C_1) with one electron transferred from Au_(32) to the antibonding pi* orbit of CO,it is bound more strongly on Au_(32)(C_1) than on Au_(32)(I_h).Spin polarized and spin nonpolarized calculations result almost identical ground state structures of Au_(32)(I_h)-O_2 and Au_(32)(C_1)-O_2,in which O_2 is dissociatively chemisorbed.