Hybrid open frameworks.: Hydrothermal synthesis, structure determinations, and magnetic behavior of (VIVO)2(H2O){O3P-(CH2)3-PO3} • 2H2O:: A new vanado-alkyldiphosphonate closely related to VO(HPO4) • 0.5H2O

((VO)-O-IV)(2)(H2O){O3P-(CH2)(3)-PO3}. 2H(2)O was hydrothermally synthesized from a mixture of VOSO4. 5H(2)O:H2PO3-(CH2)(3)-PO3H2:H2O in a molar ratio 1:0.5:250 and heated for 72 hours to 170 degreesC, Its structure was determined from powder X-ray diffraction data. It crystallizes in the orthorhombic space group Immm (No. 71) with a = 16.8210(5) Angstrom, b = 9.3790(3) Angstrom, c = 7.3568(2) Angstrom, V = 1176.4(1) Angstrom (3), Z = 4, The pillared framework is built up from inorganic layers covalently linked via P-C-C-C-P bonds, The inorganic layers are similar to those encountered in a VO(HPO4).0,5H(2)O bidimensional compound described previously. The dimers of face-shared VO5(H2O) octahedra are linked by PO3C phosphonate groups instead of PO3(OH) groups in the vanadyl hydrogenphosphate, The terminal hydroxyl groups in the latter are substituted by the carbons of the organic chains which link two layers, giving the three-dimensional character of the structure, The magnetic behaviors of the two compounds are compared. (C) 2000 Academic Press.