Preparation and single-crystal structure analysis of Ca2NF

Single-crystalline samples of Ca,NF were prepared by heating a stoichiometr ic mixture of Ca metal and CaF2 under N-2 to 1000 degreesC, followed by slo w cooling from the melt. The resulting Ca2NF crystals were yellow in color, and highly air-sensitive. A single-crystal X-ray diffraction analysis indi cated that the compound is isostructural with L-Mg2NF, with tetragonal cell parameters a = 4.9018(9) Angstrom and c = 10.516(3) Angstrom, Z = 4, and s pace group I4(1)/amd (No. 141). X-ray refinement was carried out by full-ma trix least-squares on F-2 on all data, to give R-1 = 0.0426 (all data) and wR(2) = 0.0630 for 12 parameters and 101 independent reflections. The final position assignments were analyzed via bond valence sum calculations. (C) 2001 Academic Press.