| Abstract
| - Dioxane-, trioxane-, and 18-crown-6-intercalated VOPO4 were prepared by a displacementreaction with 1-propanol-intercalated VOPO4 and characterized by powder XRD, TGA, andUV−vis, IR, and Raman spectroscopies. Depending on the temperature of the preparation,the dioxane-intercalated VOPO4 forms two compounds with formulas VOPO4·C4H8O2 (thelow-temperature compound) and VOPO4·0.5C4H8O2 (the high-temperature compound). Theformer changes to the latter by heating to 70 °C. Thermal behavior of other intercalates isalso discussed. The way the cyclic ethers are anchored to the VOPO4 layers is inferred fromthe IR and Raman spectra. The arrangement of the dioxane molecules in the interlayerspace of VOPO4 is simulated using a Cerius2 software package combined with a SUPRAMOLprogram. In VOPO4·C4H8O2, the dioxane molecules in chairlike conformation are anchoredto the VOPO4 layers via one of their oxygen atoms coordinated to the vanadium atoms,forming a bilayer in the interlayer space. For VOPO4·0.5C4H8O2, a monolayer arrangementof the dioxane molecules is proposed.
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