Intercalation studies of several layered lanthanide oxychlorides with pyridine

Abstract

Abstract A series of new intercalation compounds of the layered lanthanide oxychlorides, LnOC1 (Ln = Ho, Er, Tm and Yb), with pyridine has been successfully obtained at both room and high temperature (85 °C). The intercalated pyridine stoichiometries (χ) in the (py) x LnOCl compounds, determined by thermal gravimetric analysis, are independent of the reaction temperature and time after 2 weeks with the (py) x ErOCl and (py) x YbOCl, but are affected by the reaction temperature and time with the (py) x HoOCl and (py) x TmOCl. An average interlayer expansion of ∼5 a between the LnOCl layers upon pyridine intercalation suggests that the pyridine ring is oriented perpendicular to the host layers. The pyridine species inserted between the host layers are neutral pyridine molecules. The presence of water in pyridine leads to the pyridinium ion that also intercalates and has been identified by IR spectroscopy.