Calculated lifetimes of the first (v=1) hydrogen stretching excited state on hydrogen-covered H/Ge(111) germanium surface

In the present study, we report the calculated lifetimes of the first hydro gen stretching excited state on a hydrogen-covered H/Ge(111) germanium surf ace using molecular dynamics simulation based on the Bloch-Redfield theory. The lifetime was found to be 20 microseconds at room temperature, four ord ers longer than the hydrogen stretches on a H/Si(111) silicon surface. In a ddition, the calculations for the Ge-D and Ge-T stretches gave lifetimes in the time scale of hundreds and tens of nanoseconds, respectively, at room temperature. The thermal effect and an effect of the Ge-Ge-H bending freque ncy in the calculated lifetimes are discussed.