Correlation between structure and thermal behavior in isostructural clathrates

Two clathrates, (H)(THF)(2) and (H)(1,3-dioxolane)(2), where H is 1,4-bis[3 -(9-anthryl)propen-1-on-3-yl]benzene, were shown to be isomorphic by means of X-ray diffraction studies. In spite of the structural similarity, their thermal behavior was considerably different. The difference can be explaine d in terms of intermolecular weak forces between the host and the guest, in cluding CH/pi and O/pi interactions.