Lattice vibrations and electronic excitations in isotopically controlled diamonds

The success in the growth of man-made, isotopically controlled single crystals of (C1-xCx)-C-12-C-13 diamonds (0 less than or equal to x less than or equal to 1) has created splendid spectroscopic opportunities to address fundamental issues such as the consequences of the zero point motion and anharmonicity in lattice vibrations as well as the success and limitations of the virtual crystal approximation, the nature of electronic transitions between the bound states of accepters and the role of self energy corrections in their binding energies associated with electron-phonon interaction. Raman and Brillouin scattering and infrared spectroscopy applied to one-phonon and multi-phonon excitations as well as the Lyman transitions between the bound states of substitutional boron accepters provide illustrative examples.