Optical Emission from F$_{H}$(CN$^{-}$ ) centers in CsCl

Strong, previously unreported, emission from at least two different excited electronic states of F$_{H}$(CN$^{-})$ centers in CsCl has been measured following excitation at 532 nm, 514 nm and 568 nm. The temperature dependence of emission at 532 nm was obtained over the temperature range of 16K through 160K. No emission under excitation at 633 nm was detected. The presence of emission following excitation at the higher energies, but absent under 633 nm excitation, may suggest that the well-known energy transfer process from the electronic excited F-center states to the vibrational CN$^{-}$ energy levels in this system occurs from a single common relaxed excited electronic state associated with the absorption band at 633 nm.