Modeling in structure analysis of vanadyl phosphate intercalated with 1-alkanols

Molecular mechanics simulations supported by X-ray powder diffraction measu rements have been used to investigate the structure of vanadyl phosphate in tercalated with 1-alkanols CnH2n+1 OH for n = 2, 3, 4. Modeling revealed th e specific features and differences in arrangement of alkanol molecules wit h different chain length, depending on the relation between the parameters of active sites network and size of guest molecules. This result enabled us to explain the irregularities in dependence of basal spacing on the chain length. The comparison of experimental d(exp) and calculated d(calc) values of basal spacing showed the good agreement of modeling with x-ray powder d iffraction. While we obtained d(calc) (Univ) = 13.05 Angstrom for vanadyl p hosphate-ethanol using the Universal force field (d(exp) = 13.17 Angstrom), for vanadyl phosphate-propanol and vanadyl phosphate-butanol better agreem ent with experiment was obtained using the Tripos force field. In the case of vanadyl phosphate-propanol the calculated basal spacing d(calc) (Tripos) = 14.49 Angstrom, compared with an experimental value of d(exp) = 14.36 An gstrom. For vanadyl phosphate-butanol d(calc) (Tripos) = 17.71 Angstrom and d(exp) = 17.90 Angstrom.