New d~0 Transition Metal lodates:Synthesis,Structure,and Characterization of BaTi(IO_3)_6,LaTiO(IO_3)_5,Ba_2VO_2(IO_3)_4centre dot(IO_3),K_2MoO_2(IO_3)_4,and BaMoO_2(IO_3)_4centre dotH_2O

摘要

Five new d~0 transition metal iodates,BaTi(IO_3)_6,LaTiO(IO_3)_5,Ba2VO_2(IO_3)_4centre dot(IO_3),K_2MoO_2(IO_3)_4,and BaMoO_2(IO_3)_4centre dot H_2O,have been synthesized by hydrothermal methods using Ba(OH)_2centre dot8H_2O,La_2O_3,K_2CO_3,TiO_2,V_2O_5,MoO_3,and HIO_3 as reagents.The structures of these compounds were determined by single-crystal X-ray diffraction.All of the reported materials have zero-dimensional or pseudo-one-dimensional crystal structures composed of MO_6 (M=Ti~(4),V~(5+),or Mo~(6+)) octahedra connected to IO_3 polyhedra.Infrared and Raman spectroscopy,thermogravimetric analysis,and UV-vis diffuse reflectance spectroscopy are also presented.Crystal data:BaTi(IO_3)_6,trigonal,space group R-3 (No.148),with a=b=11.4711(10) A,c=11.1465(17) A,V=1270.2(2) A~3,and Z=3;LaTiO(IO_3)_5,monoclinic,space group P2_1 (No.14),with a=7.4798(10) A,b=18.065(2) A,c=10.4843(14) A,beta=91.742(2)deg,V=1416.0(3) A~3,and Z=4;Ba_2VO_2(IO_3)_4centre dot(IO_3),monoclinic,space group P2_1/c (No.14),with a=7.5012(9) A,b=33.032(4) A,c=7.2150(9) A,beta=116.612(2)deg,V=1598.3(3) A~3,and Z=4;K_2MoO_2(IO_3)_4,monoclinic,space group C2/c (No.15),with a=12.959(2) A,b=6.0793(9) A,c=17.748(3) A,beta=102.410-(4)deg,V=1365.5(4) A~3,and Z=4;BaMoO_2(IO_3)_4centre dotH_2O,monoclinic,space group P2_1 (No.14),with a=13.3368-(17) A,b=5.6846(7) A,c=18.405(2) A,beta=103.636(2)deg,V=1356.0(3) A~3,and Z=4.