两种砷钼杂化多酸盐的合成、结构及变色性质

Synthesis,Structure,and Allochroic Property of Two Hetro-arsenomolybdates Hybrid Polyoxometalates

分别以2种V形羧酸[1,3-苯二甲酸(H_(2)BDC)和5-羟基-1,3-苯二甲酸(H_(2)OIP)]与钼酸铵进行反应,得到了2种有机酸根与无机酸根缩合构成的杂化砷钼酸盐:(NH_(4))_(17)H_(4)[(AsMo_(6)O_(21))_(2)(AsMo_(6)O_(23))(BDC)_(4)]·28H_(2)O(1)和(NH_(4))_(5)Cs_(8)H_(6)[(AsMo_(6)O_(21))_(3)(OIP)_(5)]·40H_(2)O(2).利用单晶X射线衍射对2种化合物进行了结构分析,发现二者均为三聚结构.对2种化合物的光致变色及热致变色性质进行了研究,发现在氙灯照射下2种化合物均可在5 min内变色.当将2种化合物的样品加热到373 K时,均出现颜色变化,并随着温度升高颜色逐渐加深.光致变色与热致变色过程前后的EPR检测结果均提示化合物的颜色变化与Mo^(VI)转化为Mo^(V)有关.

Benzene-1,3-dicarboxylic acid(H_(2)BDC)and 5-hydroxy-1,3-benzene dicarboxylic acid(H_(2)OIP)have been employed to synthesis two organic-inorganic hybrid arsenomolybdates,(NH_(4))_(17)H_(4)[(AsMo_(6)O_(21))_(2)(AsMo_(6)O_(23))(BDC)_(4)]·28H_(2)O(1) and (NH_(4))_(5)Cs_(8)H_(6)[(AsMo_(6)O_(21))_(3)(OIP)_(5)]·40H_(2)O(2).X-Ray crystallographic study indicated that both of the two compounds are trimers.The photochromic properties have been studied.Under the irradiation of a Xe-lamp,the two compounds changed their colors within 5 min.The thermochromic study of the two compounds indi⁃cated that they changed color at 373 K,and their color deepened on the increase of temperature.