Synthesis and Spectroscopic Investigations of New Linear Heterobimetallic Clusters [Me4N]3[(TOS3)2Ag] (T=Mo,W). Crystal Structure of [Me4N]3[(MoOS3)2Ag]

Red-brown crystals of a new bis(thiomolybdate) complex [Me4N]3[(MoOS3)2Ag] were formed at room temperature through the reaction of a solution of [Me4N]2[MoOS3] in MeCN with solid AgCN. They are monoclinic, space group P21/c with unit cell parameters a=16.662(9), b=9.464(3), c=17.890(8)Ä, beta=101.87(2)?, Z=4. The crystal structure was determined from single crystal diffractometer data (MoKalpha-radiation)and refined to R=0.044 (3614 reflections, 236 variable parameters). The structure is characterized by trinuclear complex anions, [(MoOS3)2Ag](3-). According to Weissenberg investigations the homologous tungsten compound is isostructural. The infrared spectrum of the molybdenum complex (KBr powder) shows absorption bands at 884(vs) and 871(w)cm-1 (teminal ny(Mo-O)), 483(vs)cm-1 (terminal ny(Mo-S)), 451(vs), and 435(w)cm-1 (bridging ny(Mo-S)). The tungsten complex showed bands at 901(vs)cm-1 (terminal ny(W-O)), 478(vs)cm-1 (terminal ny(W-S)), and 435(vs)cm-1 (bridging ny(W-S)). The anionic mass spectra shows molecular ion peaks at m/z 524 and 700 for [MoOS3)2Ag](-) and [(WOS3)2Ag](-), respectively, as well as peaks for other fragments.