Dual luminescence and excited-state dynamics in Ti2+ doped NaCl

Single crystals of Ti2+ doped NaCl were grown by the Bridgeman technique. H igh resolution variable temperature absorption, continuous-wave emission, a nd time-dependent measurements were performed for the spectroscopic charact erization of the title compound. At T < 100 K excitation of Ti2+:NaCl in th e red spectral region around 647 nm results in two broad emission bands cen tered at about 1850 and 780 nm, respectively, originating from the T-3(2g)( t(2g)e(g)) first excited state and from the T-3(1g)(t(2g)e(g)) higher excit ed state, respectively. Rate constants for the individual depopulation proc esses of the two metastable excited states are determined. The calculated 1 5 K T-3(2g)(t(2g)e(g)) --> T-3(1g)(t(2g)(2)) and T-3(1g)(t(2g)e(g)) --> T-3 (1g)(t(2g)(2)) luminescence quantum yields are 1 and approximate to0.26, re spectively.