Five new do transition metal iodates, BaTi(IO3)(6), LaTiO(IO3)(5), Ba2VO2(IO3)(4)(.)(IO3), K2MoO2(IO3)(4), and BaMoO2(IO3)(4)(.) H2O, have been synthesized by hydrothermal methods using Ba(OH)(2)(.)8H(2)O, La2O3, K2CO3, TiO2, V2O5, MoO3, and HIO3 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 MO6 (M = Ti4+, V5+, or Mo6+) octahedra connected to IO3 polyhedra. Infrared and Raman spectroscopy, thermogravimetric analysis, and UV-vis diffuse reflectance spectroscopy are also presented. Crystal data: BaTi(103)6, trigonal, space group R-3 (No. 148), with a = b = 11.4711(10) angstrom, c = 11.1465(17) angstrom, v = 1270.2(2) angstrom(3), and Z = 3; LaTiO(IO3)(5), monoclinic, space group P2(1)/n (No. 14), with a = 7.4798(10) angstrom, b = 18.065(2) angstrom, c = 10.4843(14) angstrom, beta = 91.742(2)degrees, V = 1416.0(3) angstrom(3), and Z = 4; Ba2VO2(IO3)(4)(.)(IO3), monoclinic, space group P2(1)/c (No. 14), with a = 7.5012(9) angstrom, b = 33.032(4) angstrom, c = 7.2150(9) angstrom, beta = 116.612(2)degrees, V = 1598.3(3) angstrom(3), and Z = 4; K2MoO2(IO3)(4), monoclinic, space group C2/c (No. 15), with a = 12.959(2) angstrom, b = 6.0793(9) angstrom, c = 17.748(3) angstrom, beta = 102.410(4)degrees, V = 1365.5(4) angstrom(3), and Z = 4; BaMoO2(IO3)(4)(H2O)-H-., monoclinic, space group P2(1)/n (No. 14), with a = 13.3368(17) angstrom, b = 5.6846(7) angstrom, c = 18.405(2) angstrom, beta = 103.636(2)degrees, V = 1356.0(3) angstrom(3), and Z = 4.