Calcium-free Solid Solutions in the System Ba7F12Cl2−xBrx (x < 1.5), a Single-component White Phosphor Host

Abstract

We have recently prepared solid solutions of Ba∼6.3Ca∼0.7F12Cl2−xBrx with x ranging from 0 to 2. In this work, the synthesis and single crystal X-ray structure of calcium-free crystals of Ba∼6.9Na∼0.2F12Br0.6Cl1.4 (space group P63/m, a = 10.6024(10), c = 4.2034(4) Å), Ba∼6.9Na∼0.2F12Br1.4 Cl0.6 (space group P63/m, a = 10.6155(9), c = 4.2355(4) Å) and Ba∼6.9Na∼0.2Br1.32Cl0.68F12 (space group P63/m, a = 10.6218(9), c = 4.2284(4) Å) are reported. These crystals systematically present additional electron density at the 0 0 0.25 position which is associated with the presence of small, but significant amounts of Na+ ions in the crystal.