[Vibronic coupling parameters and luminescent properties of bivalent europium ion doped alkaline earth thioaluminates].

To obtain blue and green electroluminescent phosphor of high efficiency, vibronic coupling parameters and luminescent properties of M(II) Al2 S4 : Eu materials were researched. Configuration coordinate model, which is the base of assessment, was introduced and assessing parameters were listed firstly. Photoluminescent (PL) and electroluminescent (EL) properties of M(II) Al2S4 : Eu were compared and analyzed by the PL and EL spectra. Additionally, performances of M(II) Al2S4 : Eu phosphor materials were evaluated with the calculation of characteristic energy and unitless factors by PL spectra. According to the result of assessment and the comparison of CIE1931 color coordinates, it can be concluded that BaAl2 S4 : Eu and CaAl2 S4 : Eu are suitable for blue and green emitting phosphor. Mg and Sr thioaluminates can be used as parts of complex thioaluminate phosphors because they can shift the emission peaks.