Oliver S. Wenger and Hans U. Güdel
Dual Luminescence and Excited-State Dynamics in Ti²⁺ Doped NaCl
J. Phys. Chem. B 105, 4181-4187 (2001)                 

Abstract: Single crystals of Ti²⁺ doped NaCl were grown by the Bridgeman technique. High resolution variable temperature absorption, continuous-wave emission, and time-dependent measurements were performed for the spectroscopic characterization of the title compound. At T < 100 K excitation of Ti²⁺:NaCl in the red spectral region around 647 nm results in two broad emission bands centered at about 1850 and 780 nm, respectively, originating from the ³T_2g(t_2ge_g) first excited state and from the ³T_1g(t_2ge_g) higher excited state, respectively. Rate constants for the individual depopulation processes of the two metastable excited states are determined. The calculated 15 K ³T_2g(t_2ge_g) ³T_1g(t_2g²) and ³T_1g(t_2ge_g) ³T_1g(t_2g²) luminescence quantum yields are 1 and 0.26, respectively.