Structure determination and a vibrational study for the hexagonal elpasolite Cs2NaGaF6:Cr3

Autor: Geoffrey F. Strouse, A. Dias Tavares, Lilian P. Sosman, R. J. M. da Fonseca, Khalid M. Hanif, Heloisa N. Bordallo, Xiaoping Wang
Rok vydání: 2002
Předmět:
Zdroj: Journal of Physics: Condensed Matter. 14:12383-12389
ISSN: 0953-8984
DOI: 10.1088/0953-8984/14/47/312
Popis: Single crystals of 0.5% Cr3+-doped Cs2NaGaF6 were studied by means of x-ray diffraction and polarized Raman scattering. The crystal exhibits a unique stacking interaction, with a hexagonal structure with Rm symmetry. Polarized Raman spectra recorded at 16 and 300 K reveal sidebands that are ascribed to the local vibrational of the [CrF6] coordination unit, which differ markedly from those of the Cs2NaGaF6 host lattice. The results are compared to findings for other elpasolite lattices, and the room temperature luminescence quantum yields are discussed in terms of a delicate balance between electron–phonon strength and lattice distortion.
Databáze: OpenAIRE