Artigo
Mechanisms behind blue, green, and red photoluminescence emissions in CaWO4 and CaMoO4 powders
Fecha
2007-07-30Registro en:
Applied Physics Letters. Melville: Amer Inst Physics, v. 91, n. 5, 3 p., 2007.
0003-6951
10.1063/1.2766856
WOS:000248595800051
WOS000248595800051.pdf
Autor
Universidade Estadual Paulista (Unesp)
Universidade Federal de São Carlos (UFSCar)
Universidade de São Paulo (USP)
Resumen
A combined experimental and theoretical study was conducted to analyze the photoluminescence (PL) properties of ordered and disordered CaWO4 (CW) and CaMoO4 (CM) powders. Two mechanisms were found to be responsible for photoluminescence emission in CW and CM powders. The first one, in the disordered powders, was caused by oxygen complex vacancies [MO3 center dot V-O(x)], [MO3 center dot V-O(center dot)] and [MO3 center dot V-O(center dot center dot)], where M=W or Mo, which leads to additional levels in the band gap. The second mechanism, in ordered powders, was caused by an intrinsic slight distortion of the [WO4] or [MoO4] tetrahedral in the short range. (c) 2007 American Institute of Physics.