An unusual fan-type polyanion with a silver cation located at the axial center, [AgAs2III((AsAsMo4O18)-As-III-Mo-V(OH)(2))(3)](11-)

作者：Ma Ying; Xue Qi; Min Suotian; Zhang Yanping; Hu Huaiming; Gao Shengli; Xue Ganglin^*

来源：Dalton Transactions, 2013, 42(10): 3410-3416.

DOI：10.1039/c2dt32401f

A new type of polyoxomolybdate containing mixed-valence arsenic, [AgAs2III((AsAsMo4O18)-As-III-Mo-V(OH)(2))(3)](11-) (1), has been synthesized. Single-crystal X-ray analysis was carried out on (NH4)(5)(C2H9N2)(4.5)H-1.5[AgAs2III((AsAsMo4O18)-As-III-Mo-V(OH)(2))(3)]center dot 14H(2)O (1a) and (NH4)(11)[AgAs2III((AsAsMo4O18)-As-III-Mo-V(OH)(2))(3)]center dot 16H(2)O (1b). The polyanion is composed of three unprecedented [(AsAsMo4O18)-As-III-Mo-V(OH)(2)](6-) subunits linked together by two AsO3 trigonal-pyramidal structures from both sides via sharing six bridging oxygen atoms, and a silver cation is enclosed in the center of the polyanion and coordinated by three As atoms with the As-Ag-As bond angle of 120 degrees, to lead to a fan-like structure with an approximative C-3h symmetry. The polyanion was also characterized by IR, X-ray photoelectron spectroscopy and thermogravimetry-differential scanning calorimetry. The stability of [AgAs2III((AsAsMo4O18)-As-III-Mo-V(OH)(2))(3)](11-) in an aqueous solution was investigated by electronic absorbance spectroscopy and electrospray ionization mass spectrometry, and the possible disaggregation mechanism of the polyanion is proposed.

• 出版日期2013
• 单位西北大学; 陕西理工大学