Crystal structure determination of Ag2Ga by single crystal X-ray diffraction

The crystal structure of zeta'-Ag2Ga has been determined by single crystal X-ray diffraction at 293 K and 150 K. The structure is hexagonal with the non-centrosymmetric space group P (6) over bar 2m (no. 189). The cell dimensions are a = 0.77680(16) nm, c = 0.28759(6) nm at 293 K and a = 0.77460(16) nm, c = 0.28704(5) nm at 150 K. zeta'-Ag2Ga has the InMg2 type of structure with nine atoms (six Ag and three Ga) on four different atomic sites (3f, 3g, 1b and 2c). The Ag atoms fully occupy the 3f and 3g positions and the Ga atoms the 1b and 2c positions. The structure parameters (atomic positions and anisotropic thermal parameters) were refined using data collected on a Siemens SMART CCD SYSTEM. The composition of the single crystals was determined by Energy Dispersive X-ray Spectroscopy (EDS) in a Scanning Electron Microscope (SEM).