title: Intercalation of 1,n-diols into strontium phenylphosphonate: how the shape of the host layers influences arrangement of the guest molecules.
abstract: Strontium phenylphosphonate intercalates with 1,n diols (n=2-4, 6-8) having general formula SrC6H5PO3⋅x(HO(CH2)nOH)⋅yH2O were prepared by precipitation from strontium phenylphosphonate solution and the corresponding diols. Prepared compounds exhibit a very good stability at ambient conditions. The intercalates were characterized by X-ray diffraction, thermogravimetry and elemental analysis. Thanks to the existence of free spaces among the benzene rings the diols exhibit a peculiar intercalation behavior. This behavior is explained on the basis of molecular simulation, which facilitated to elucidate the arrangement of the diol (guest) molecules in the specifically shaped space between the layers of the host material. From the structural point of view the intercalates can be divided into two subgroups: (i) intercalates with 1,2- to 1,4-diols and (ii) intercalates with 1,6- to 1,8-diols. The alkanediols of the first group are immersed in the free spaces among the benzene groups, their molecules adopt a horseshoe shape meaning cis conformation and are bonded by both of their OH groups to one host layer. The longer alkanediol chains of the second group allow anchoring to both neighboring layers of the host forming a kind of pillared structure in the interlayer space. The diol molecules are in this case bonded to the host layers by their OH groups to the oxygen atoms of the host layers and to water molecules present in the interlayer space through hydrogen bonds. The values of the basal spacing obtained from the experimental powder X-ray patterns are in a very good agreement with the basal spacing values calculated from the models. The molecular simulation of a 1,5-pentanediol intercalate, which we were not be able to synthesize, explained why this intercalate cannot be stable.
authors: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic(2).
authors: Klára
authors: K
authors: Melánová
authors: Charles University in Prague, Faculty of Mathematics and Physics, Department of Chemical Physics and Optics, Ke Karlovu 3, 121 16 Prague 2, Czech Republic.
authors: Petr
authors: P
authors: Kovář
authors: Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic.
authors: Ludvík
authors: L
authors: Beneš
authors: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic(2).
authors: Jan
authors: J
authors: Svoboda
authors: Charles University in Prague, Faculty of Mathematics and Physics, Department of Chemical Physics and Optics, Ke Karlovu 3, 121 16 Prague 2, Czech Republic.
authors: Marek
authors: M
authors: Veteška
authors: Charles University in Prague, Faculty of Mathematics and Physics, Department of Chemical Physics and Optics, Ke Karlovu 3, 121 16 Prague 2, Czech Republic. Electronic address: pospisil@karlov.mff.cuni.cz.
authors: Miroslav
authors: M
authors: Pospíšil
authors: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic(2).
authors: Vítězslav
authors: V
authors: Zima
keywords: Alkaline-earth metals; Intercalation; Molecular modeling; Phosphonates