Crystal structure of europium lithium gallium, EuLi0.24Ga1.76

Abstract

EuGa1.76Li0.24, orthorhombic, Imma (no. 74), a = 4.6433(4) A, b = 7.6322(6) A, c = 7.7341(7) A, V = 274.1 A 3 , Z =4 , Rgt(F) = 0.037, wRref(F) = 0.098, T = 293 K. Source of material A set of bulk samples around the composition EuLixGa2–x was prepared from the elements. Lithium (99.9 mass %, Alfa) and gallium (99.99 mass %, ChemPur) were used as delivered, whereas europium (99.9 mass %, ChemPur) was re-distilled before use. Mixtures of elements with total mass of approximately 1.5 g were welded in niobium tubes and placed in the evacuated and sealed quartz ampoules. To prevent reaction of europium and lithium with air and moisture, all manipulations of educts and products were performed inside an argon-filled glove box (p(O2 ,H 2O) < 1 ppm, purification by molecular sieve and copper catalyst). At the first step of the synthesis, the ampoules were slowly heated to 900 °C within 24 h and held at this temperature for 2 h. After that, the temperature was decreased within one day to 300 °C. Subsequently, the samples were annealed at this temperature for 30 d and then quenched in cold water. A single crystal with irregular shape suitable for data collection was mechanically extracted from the sample with nominal composition Eu30Li30Ga40 and encapsulated into a glass capillary. Experimental details For calculation of interatomic distances, the lattice parameters were used as obtained from X-ray powder diffraction data (Image Plate Guinier Camera HUBER G670, Co K1 radiation, = 1.788965 A, silicon as internal standard, a = 5.43102 A).