Catalytic ammonia synthesis on HY-zeolite-supported angstrom-size molybdenum cluster.

The development of new catalysts with high N activation ability is an effective approach for low-temperature ammonia synthesis. Herein, we report a novel angstrom-size molybdenum metal cluster catalyst for efficient ammonia synthesis. This catalyst is prepared by the impregnation of a molybdenum halide cluster complex with an octahedral Mo metal core on HY zeolite, followed by the removal of all the halide ligands by activation with hydrogen.

Syntheses, Structures, FAB Mass Spectra, and Magnetic Properties of Chromium Chalcogenide Cluster Complexes [Cr(6)Se(8)(PEt(3))(6)], [Cr(6)Se(8)(H)(PEt(3))(6)], and [Cr(6)S(8)(H)(PEt(3))(6)].

Chromium selenide cluster complexes [Cr(6)Se(8)(PEt(3))(6)] (1) and [Cr(6)Se(8)(H)(PEt(3))(6)] (2) were prepared by the reaction of anhydrous chromium dichloride, Na(2)Se(x)(), and triethylphosphine in methanol. A similar procedure except for the use of NaS(x)()H in place of Na(2)Se(x)() gave a sulfide cluster complex [Cr(6)S(8)(H)(PEt(3))(6)] (3). The partly deuterated derivative [Cr(6)S(8)(D)(0.