Preparation and thermophysical properties of AgGaTe2 crystals

The preparation and thermophysical properties of AgGaTe2 crystals are reported. The synthesis from pure elements was performed in a rocking oven and scanning electron microscopy and energy dispersive X-ray elemental analysis show the presence of additional phases. From simultaneous differential calorimetry and thermogravimetric analysis (SDT) measurements we have found that AgGaTe2 melts at 725.7 degreesC, with a heat of fusion of 104.8J/g(-1). High temperature powder X-ray diffraction data confirmed the chalcopyrite structure and yielded the thermal expansion coefficients along the a- and c-axes to 500 degreesC. Heating above that temperature, under inert gas flow, causes the material to sublime incongruently and produce a film of gallium rich surface. Experimental values of thermal diffusivity and estimates of the thermal conductivity values are also presented. (C) 2001 Elsevier Science B.V. All rights reserved.