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Updated: May 21, 2026

Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
Double perovskite structure: a vibrational and luminescence investigation providing a perspective on crystal field
Wenyu Li1, Lixin Ning, Peter A Tanner
1Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong S.A.R., P. R. China.
Abstract:
The luminescence spectra of Eu(3+) doped in a series of double perovskite lattices Ba(2)LnMO(6) (Ln = Y, Gd; M = Nb, Ta) have been recorded at room temperature and 10 K. Together with FT-IR and FT-Raman spectra and aided by DFT vibrational energy calculations, assignments have been made for the crystal field levels of the (5)D(J) (J = 0,1) and (7)F(J) (J = 0-2) multiplets. The luminescence spectra are consistent with monoclinic symmetry of these systems. The crystal field parameters from the fitting of the energy level data set of Ba(2)YNbO(6):Eu(3+) enable the crystal field strength to be calculated, and the order of magnitude is Cl(-) < O(2-) < F(-) for the EuX(6)(n-) (n = 6 for halogen, 9 for oxide) moieties. For these systems, an empirical linear relationship between crystal field strength and electronegativity of ligand X has been found. By contrast, the nephelauxetic series from the depression of the Slater parameter F(2) is Cl(-) ≈ O(2-) > F(-) > free ion for these systems.
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