| Abstract
| - Confocal Raman microspectrometry has been applied as an in situ probe of the transport of guest moleculesalong the one-dimensional tunnels in a crystalline urea inclusion compound, under conditions of guest exchangein which “new” guest molecules (pentadecane) are introduced at one end of the tunnel and displace the“original” guest molecules (1,8-dibromooctane). The Raman spectra, recorded as a function of position alongthe tunnel direction and as a function of time, demonstrate that the transport process is associated with asignificant change in the conformational properties of the original (1,8-dibromooctane) guest molecules. Inparticular, in the boundary region between the original and new guest molecules, there is a substantial increasein the proportion of 1,8-dibromooctane guest molecules that have the gauche end-group conformation. Thewider implications of this observation are discussed in relation to fundamental aspects of the molecular transportprocess in this material.
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