Synthesis and crystal structure of an organic-inorganic composite phosphotungstate[HTA]_3[α-PW_(12)O_(40)]·6H_2O

An organic-inorganic composite Keggin-type phosphotungstate[HTA]3[α-PW12O40]·6H2O(TA=1,2,4-triazole)was synthesized viathe reaction of CuCl2·2H2O,Na3[α-PW12 O40]·6H2O,and L-serine with 1,2,4-triazole in aqueous solution of ethanol.The structure of as-synthesized product was characterized by infrared spectrometry and single-crystal X-ray diffraction,and its composition was determined by elemental analysis.It was found that the title compound crystallizes in the rhombohedral space group R-3with a = 1.793 73(12)nm,b = 1.793 73(12)nm,c=2.440 7(3)nm,α =β= 90°,γ =120°,Z =6,V = 6.800 7(11) nm3,Dc =4.682g·cm-3,GOOF =1.079,R1 =0.051 6and wR2 =0.137 4.In terms of the molecular structure,the title compound consists of one saturated Keggin phosphotungstate[α-PW12 O40 ]3-anion,three free monoprotonated[HTA]+cations and six lattice water molecules.