A New Modification of Tellurite Phosphate: β-Te3O3(PO4)2

摘要

A new modification of tellurite phosphate,β-Te3O3(PO4)2,has been synthesized under hydrothermal conditions and its crystal structure was determined by single-crystal X-ray diffraction.It crystallizes in the monoclinic space group P21/n (No.14),with a =11.115(5),b =4.7033(19),c =17.287(7) (A),β =106.086(5)°,V=868.3(6) (A)3,Z=4,P2Te3O11,Mr =620.74,Dc =4.748 g/cm3,μ(MoKa) =10.438 mm-1 and F(000) =1096.The final full-matrix least-squares refinement converged to R =0.0227,wR =0.0534 for 1984 observed reflections with I ＞ 2σ(I),and R =0.0240,wR =0.0540 for all data (2070) and S =1.117.β-Te3O3(PO4)2 is polymorphic with the known α-Te3O3(PO4)2 (Weil H.M.et al.Z.Anorg.Allg.Chem.2003,629,1068-1072).The crystal structure of β-Te3O3(PO4)2 features a three-dimensional (3D) network composed of Te6O2220-hexanuclear clusters interconnected by PO4 groups.Te6O22 hexanuclear cluster is built from three Te2Os dimers (edge-sharing TeO5 square pyramids) linked to each via sharing O-corners.The structure difference between α-and β-forms of Te3O3(PO4)2 lies in the polymerization of tellurite oxides TenOm.1D infinite 1∞{[Te3O11]10-} single chains are presented in α-Te3O3(PO4)2,while 0D discrete Te6O22 hexanuclear clusters are observed for β-Te3O3(PO4)2.Moreover,thermal analyses,infrared spectra and UV-Vis-NIR diffuse reflectance are also presented.