Study on the local compressibility of (MnF6)2− centres in KNaSiF6: Mn4+ red phosphor material by analysing its pressure-induced spectral line shifts

Abstract

The local linear compressibility of (MnF6)2− centres in KNaSiF6: Mn4+ red phosphor material is estimated by analysing its pressure-induced R-line red-shift. The result is confirmed by calculating the pressure-induced E(4T2)-line blue-shift. The evaluated local linear compressibility of (MnF6)2− impurity centres is much smaller than the linear compressibility of host KNaSiF6 crystal as a whole obtained from the theoretical calculation. The causes (i.e., the local compressibility of impurity cluster being smaller than the corresponding host one, and the local compressibility of the corresponding host cluster being also smaller than the compressibility of whole crystal) about the difference between the local compressibility of (MnF6)2− impurity centre and the compressibility of whole host KNaSiF6 crystal are discussed.