C-13 CP/MAS spectroscopy of calixarene-based carceplexes shows that
in the solid state the cavity walls of the carcerand are rigid, where
as the pendant groups of the resorcinarene as well as the ends of t
he propyl goups of the calixarene moiety exhibit some flexibility.
Temperature dependent H-2 measurements of the DMSO-d(6) carceplex reve
al that two different sites are present for the DMSO guest with an ene
rgy difference of 1.7 kcal mol(-1).