摘要
Three new vanadyl gallium phosphates, (H 2 dap)3[(VO) 2 (GaO) 2 (PO 4 )4] • H 2 O (1), (H 2 dap) 1.5 [(VO) 2 (GaO) 2 -(PO 4 ) 3 ].3H 2 O (2), and (H 2 dap)[(VO) 2 Ga 4 (PO 4 ) 6 (H2O) 4 ].2H 2 O (3) (dap = 1,3-diaminopropane), have been prepared under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, magnetic susceptibility, and EPR spectroscopy. They are the first examples of an organic/V 4+ /Ga/P/O system that displays three different dimensional structures with a common template. The 1D chain structure of 1 and the 2D layered 2 are both built up with a PO 4 and {V 2 Ga 2 O 14 } cluster which contains a syn-square pyramidal {V 2 O 8 } dimer and two GaO 4 tetrahedra. The tetrameric cluster and V-O-Ga therein are observed in a metal phosphate system. Compound 3 is composed of VO 5 (H 2 O) octahedra, GaO 4 (H 2 O) trigonal bipyramids, and GaO 4 and PO 4 tetrahedra from which a unique 3D structure containing one-dimensional 12-ring channels is constructed. The channel aperture uncommonly comprises heterometal (V, Ga) polyhedra. Magnetic susceptibility data for 1-3 are consistent with V 4+ and show a T N of 12 K for 3. The unusual syn-{V 2 O 8 } dimers in 1 and 2 induce superexchange interactions, while isolated VO 5 (H 2 O) octahedra in 3 display super-super-exchange interaction. Electron paramagnetic resonance spectra with 51 V hyperfine structures were distinctly observed at 300 K for 1, while they started emerging at 30 K for 2 and 7 K for 3. The average hyperfine constant, 85.56 Gauss,was obtained via spectral simulations and nonlinear least-squares fittings for 1 and 2. Crystal data for 1 are triclinic, P1̄, a = 9.1754(4) Å, b = 10.7853(5) Å, c= 15.6519(7) Å, α = 93.251 (1)°, β = 92.530(1)°, γ = 95.106(1)°, V= 1538.4(1) Å 3 , and Z= 2; for 2, monoclinic, P2 1 /n, a=8.9195(3) Å ,b= 14.6374(5) Å, c= 17.8608(6) Å, β = 97.272(1)°, V= 2313.1(1) Å 3 , and Z=4; and for 3, monoclinic, P2 1 /c, a = 9.0970(5) Å, b= 16.9940(9) Å, c = 9.6441(5) Å, β = 103.456(3)°, V= 1450.0(1) Å 3 , and Z=4. © 2009 American Chemical Society.