Crystal growth and mechanical characterization of ZrMo2O8

We report a fluxing technique for ZrMo2O8 single crystal growth. The volatility of MoO3 coupled with the limited temperature range of its stability with the liquid phase makes the single crystal growth of ZrMo2O8 a formidable challenge. Single crystal growth of ZrMo2O8 was carried out in a horizontal tubular furnace using a platinum boat and utilizing Li2MoO4 as a fluxing agent. The synthesized faceted crystals were up to 3 mm along the maximum dimension. Laue and single crystal X-ray diffraction confirmed the monoclinic crystal structure having a space group C 1 2/c 1 (S.G#15), and a single crystallographic domain within the crystals. Reduced elastic modulus and hardness were determined to be 108±4 GPa and 6.4±0.2 GPa respectively using nanoindentation. Appearance of additional peaks in Raman spectra of the indented region when compared with the fresh crystal indicated a possible pressure induced phase transformation during indentation.