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measurements a r e performed a t 53 and 279 K . T?ie e m i s s i o n i s e x c i t e d photons w i t h d i f f e r e n t e n e r g i e s i n t h e r e g i o n o f t h e a c t i v a t o r ' s a b s o r p t i o n . Two bands are o b s e r v e d i n t h e spectrum t h e i n t e n s i t i e s o f which depend on t h e t e m p e r a t u r e and t h e e x c i t a t i o n e n e r g y . The symmetry o f t h e c e n t r e s -a s s o c i a t e s ( T l + V + ) t h e f o r m a t i o n of which i s p o s s i b l e i n t h e c r y s t a l p h o s p h o r is d e t e rmined? The e m i s s i o n o f t h e c r y s t a l p h o s p h o r BaCl -T 1 i s s t u d i e d . A l l t h e w i t h

The luminescence of BaClThe results indicate the coexistence of centres of different structure and composition. The Jahn- Teller effect might also take place