Surface Energy Estimation of Catalytically Relevant fcc Transition Metals Using DFT Calculations on Nanorods

The use of nanorods is presented to investigate the properties of low coordination atoms in a metal with an fcc structure. Calculations on nanorods can be performed in a similar manner to surface calculations keeping the efficiency of the 3D periodic plane wave approach. Nanorods with fcc(100) surfaces exposed have been used to calculate the excess energy of low coordination atoms. It was observed that the excess energy per “broken bond” decreases with an increase in the coordination number. The excess energy is further reduced due to relaxation of the surface atoms. Surface magnetization results in a further reduction of the excess energy for magnetic materials, such as Co, but not for nonmagnetic materials, such as Rh. Furthermore, it is shown that the bond strength of the surface atoms with nearest neighboring atoms in surface and bulk increase with a decrease in the coordination.