Cadmium vacancy passivated by two hydrogen atoms in CdSe.

Two previously reported local vibrational modes (LVMs) in CdSe single crystals at 1992 and 2001 cm-1 [Chen et al., Phys. Rev. Lett. 101, 195502 (2008)] are generated in the present study by annealing the crystals in H2 gas at 500 °C. The absorption bands shift to 1454 and 1461 cmwhen the samples were annealed in ambient D2. Each LVM consists of at least five lines. The relative intensities match the natural abundance of the predominant Se isotopes. The 1992- and 2001-cm"' lines are assigned to two selenium-hydrogen vibrations in the Cd vacancy. [ABSTRACT FROM AUTHOR]