Absorption and emission spectra of Ce3+ in elpasolite lattices.
The experimental determination of the electronic energy levels for Ce(3+) in some chloroelpasolite hosts for both the ground 4f(1) and the excited 5d(1) configurations is described. High-resolution f-f absorption and f-(2)T(2g) d absorption and emission spectra have been recorded at low temperatures for Ce(3+) diluted into various hexachloroelpasolite lattices. A fluorescence spectrum at approximately 50 000 cm(-1) is tentatively assigned to the emission from the highest 5d crystal field level, (2)E(g), of a Ce(3+) impurity in Cs(2)NaErCl(6), enabling the values of all the energy levels of both the 4f(1) and 5d(1) configurations to be given for Ce(3+) in elpasolite hosts. Vibronic structure superimposed on the electronic transitions is analyzed in terms of a simple configurational coordinate model involving the ground and excited configurations. It is found that the difference in the Ce-Cl bond length between the 4f(1) and 5d(1) configurations is approximately 0.04 A. Ab initio model potential calculations on the (CeCl(6))(3-) cluster embedded in a reliable representation of the Cs(2)NaYCl(6) host support these conclusions.
Tanner
Peter A
PA
Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, Peoples' Republic of China. BHTAN@cityu.edu.hk
Mak
Chris S K
CS
Edelstein
Norman M
NM
Murdoch
Keith M
KM
Liu
Guokiu
G
Huang
Jin
J
Seijo
Luis
L
Barandiarán
Zoila
Z