Surface atomic structure of the absorption of Pt on Ge(001)

We perform first principles total energy calculations to investigate the atomic structure of the adsorption of Pt on Ge(001) surfaces. Our studies are carried out using the periodic density functional Theory. The exchange and correlation energies are treated within the generalized gradient approximation according to the Perdew, Burke, Ernzerhof revised parameterization. The initial atomic structure is studied using molecular mechanics as implemented in the Forcite program of the Materials Studio^copycode. Afterwards we relax the atomic geometry using Castep. The reconstruction is in quasi-one dimensional structures. Results show the formation of nanowires on the Ge surface with periodicity b(2times1). These nanowires are composed of Pt dimers along the trenches between rows of Ge dimers. Our calculated STM images agree quite well with recent experimental results.