论文部分内容阅读
采用酸化-回流-乙醚萃取法合成了二十种Dawson结构钼砷杂多酸及其盐,元素分析确定了它们的组成,其通式为M_xAs_2Mo_(18)O_(62)·H_2O,酸碱及电导滴定确定了碱度,系统地研究了它们的红外光谱、紫外光谱、极谱、循环伏安、热重-差热分析等性质,给出了杂多阴离子As_2Mo_(18)O_(62)~(6-)在水溶液中的氧化还原机理,讨论并指认了紫外吸收为e→e~*和e→b_2的荷移跃迂谱带。考察了抗衡离子M~(n+)对主要红外振动光谱、热分解温度及其分解产物的影响。
Twenty kinds of Dawson molybdenum-arsenic heteropolyacids and their salts were synthesized by acid-reflux-ether extraction. Their compositions were determined by elemental analysis. The general formula was M_xAs_2Mo_ (18) O_ (62) .H_2O. The basicity was determined by conductometric titration. Their properties of infrared spectroscopy, UV spectroscopy, polarography, cyclic voltammetry and TG-DTA were systematically studied. The heteropolyanions As_2Mo_ (18) O_ (62) ~ (6-) redox mechanism in aqueous solution, discussed and identified the UV absorption of e → e ~ * and e → b_2 of the charge-transfer band. The effects of counterion M ~ (n +) on the main infrared spectra, thermal decomposition temperature and their decomposition products were investigated.