Structure determination of two intercalated compounds VOP4 center dot(CH2)(4)O and VOPO4 center dot OH-(CH2)(2)-O-(CH2)(2)-OH; synchrotron powder diffraction and molecular modelling

The crystal structures of two intercalated compounds have been determined u sing a combination of synchrotron powder diffraction and molecular mechanic s simulations: (1) vanadyl phosphate intercalated with tetrahydrofuran. VOP O4(CH2)(4)O. and (2) vanadyl phosphate intercalated with diethylene glycol, VOPO4HO . (CH2)2(O)(CH2)(2)OH. Both intercalates preserve the tetragonal s pace group P4/n, as found in the host structure VOPO4. 2H(2)O. (1): a = 6.2 08, c = 8.930 Angstrom, Z = 2, D-x = 2.51 g cm(-3); (2): a = 6.223, c = 11. 417 Angstrom, Z = 2, D-x = 2.66 g cm(-3). Both intercalates exhibit the: sa me type of orientational disorder in the arrangement of guest molecules, as observed in the same host compound intercalated with water. These two inte rcalates also exhibit, rather surprisingly, perfect ordering in layer stack ing without the displacement disorder, characteristic of many intercalated layered structures. Thanks to this regularity in the arrangement of guests and layers, synchrotron powder diffraction could be used in the present str ucture determination. The present results also enabled the analysis of the effect of geometrical parameters characterizing the mutual host-guest compl ementarity and the effect of host-guest and guest-guest interaction on the crystal packing of intercalates.