Weak polar host–guest interactions stabilizing a molecular cluster in a cyclodextrin cavity: C–H ⋯ O and C–H ⋯π contacts in β-cyclodextrin–but-2-yne-1, 4-diol heptahydratet

In the crystalline title complex, the guest molecules are ordered and the inclusion geometry is stabilized by a system of host–guest O–H ⋯ O, C–H ⋯ O and C–H ⋯π contacts; this is an example of weak but crucial polar interactions between the surface of a cyclodextrin cavity and a cluster of polar guest molecules.