Structural description and properties of Mg2Al-layered double hydroxides intercalated with the fluvastatin anions solved by molecular simulation methods

M. Pšenička, M. Pospíšil

Charles University, Faculty of Mathematics and Physics, Ke Karlovu 3, 121 16 Prague 2, CZ

pospisil@karlov.mff.cuni.cz

We present the structure analysis of Mg2Al layered double hydroxides intercalated by fluvastatin anions based on published experimental data and show the advantages of molecular simulation methods for description of complex organo-clay hybrid materials. Models with different arrangements of intercalated fluvastatin anions, which fully compensate the positive charge of the LDH layers, were calculated. All presented models were analysed by calculated XRD patterns, basal spacing, and free volumes calculations to describe different behaviour and properties between individual models with different arrangement of the fluvastatin anions. Based on total energy values bilayer and pseudobilayer models are preferred with respect to monolayer models. Calculated results were thoroughly compared to published experimental data and a detail comparison between experimental and calculation X-ray data is presented. It was shown that calculated patterns for monolayer and bilayer arrangement do not reach a good agreement with experimental diffraction data so as the basal spacings. In opposite of this calculated XRD patterns proved a pseudobilayer arrangement with mixture of flat and tilted positions of fluvastatin anions in the interlayer space as well as equal distribution of water molecules in the interlayer among fluvastatin anions.