Intercalation behavior of barium phenylphosphonate

The dependence of basal spacing and water content of BaC₆H₅PO₃·xH₂O on the relative humidity was studied. Intercalates of 1-alkylamines (C₂-C₁₀) and 1-alkanols (C₃-C₁₀) were prepared from barium phenylphosphonate dihydrate and also from anhydrous host and characterized by powder X-ray diffraction and thermogravimetric analysis. The intercalates of alkanols and alkylamines prepared from dihydrate are quite stable at ambient conditions and contain one guest molecule per formula unit. The guest molecules are probably arranged in monomolecular way and are perpendicular to the host layers in the case of amines or tilted to the host layers at an angle of about 80° in the case of alkanols. The intercalates prepared from anhydrous host are unstable and their basal spacings indicate parallel arrangement of the guests chains. Formation of mixed intercalates was not observed when barium phenylphosphonate dihydrate was contacted with a mixture of alkanols or amines.