A natural mineral, lindgrenite Cu3 ( MoO4 )2 ( OH)2, was synthesized from a mixture of sodium molybdate, copper sulfate, and morpholine in water under autogenous pressure at 170 ℃. The crystal structure of the mineral was determined and the final refinement for 791 observed reflections with Ⅰ 〉 2σ(Ⅰ) gave R1 = 0. 0205 and wR2 = 0. 0496. The thermal stability of the mineral was investigated by using TG-DTA and variable-temperature in situ X-ray diffraction(XRD) techniques. The crystalline Cu3Mo2O9 was obtained when the mineral underwent thermal dehydration at a temperature ranging from 300 to 400 ℃, and the mixture of MoO3 and CuO was formed through decomposition of Cu3Mo2O9 at a temperature ranging from 650 to 700 ℃. Therefore, the structure of the mineral was thermally unstable at above 300 ℃, suggesting that Lindgrenite was likely formed via the hydrothermal route occurring in the nature.
BAO Ren-lieKONG Zu-pingGU MinYUE BinWENG Lin-hongHE He-yong