Temperature-dependent photoluminescence properties of MnF2: Configurational-coordinate model analysis

A white MnF2 powder is synthesized by chemical etching of Mn shots in an aqueous HIE solution. The optical properties of this synthesized powder are investigated using photoluminescence (PL) analysis, PL excitation spectroscopy, diffuse reflectivity, and PL decay measurements. The MnF2 powder exhibits PL peaks in the red (similar to 600 nm) and infrared spectral regions (similar to 780 nm) under visible to ultraviolet excitation. These PL peaks are asymmetric with a tail on the long-wavelength side. Such spectral features and temperature-dependent PL intensities are well interpreted by a newly developed model with Huang-Rhys's factor as the electron-local vibration coupling strength. The ground-and excited-state energy level diagram for the Mn2+ ions in MnF2 is also proposed. (C) 2011 American Institute of Physics. [doi:10.1063/1.3592156]