Wydział Chemii

Mirosław Karbowiak

Jakub Cichos

Czesław Rudowicz

2012

Journal of Physical Chemistry A

116

10574-10588

10.1021/jp308539y

Naukowa

Angielski

Artykuł

Absorption emission and excitation spectra are measured and analyzed to achieve assignments of energy levels for 4f^N ions in Ba₂YCl₇:RE³⁺ (RE = Pr, Nd, Tb, Dy, Ho, Er, and Tm) crystals. The experimental energy levels were analyzed in terms of the usual free-ion parameters and the crystal field (CF) ones, B_kq, in the Wybourne notation. The orthorhombic C_2v symmetry is shown to be a good approximation of the actual triclinic C₁ site symmetry at the metal center. The starting values of the CF parameters B_kq used for fittings for the studied crystals were obtained from superposition model analysis. A good agreement between the calculated and experimental energy levels was obtained with rms deviations in the range from 6.8 cm^–1 (for Ho³⁺) to 14.1 cm^–1 (for Pr³⁺). The fitted sets of B_kq parameters are, in general, consistent across the 4f^N series. This study has enabled determination and discussion of the trends in variation of the free-ion parameters and CF ones across the 4f^N series. The CF parameter set and energy level structure obtained for Nd³⁺ ion in Ba₂YCl₇ crystal are consistent with those for Nd³⁺ in structurally related RbY₂Cl₇ crystal. This systematic analysis of CF parameters is one of only few such studies encompassing nearly whole series of RE³⁺ ions.

http://dx.doi.org/10.1021/jp308539y

https://www.acs.org/content/acs/en.html