  We study correlations in spatial orientation between galaxy clusters and
their host superclusters using a Hubble Volume N-body realization of a
concordance cosmology and an analytic model for tidally-induced alignments. We
derive an analytic form for distributions of the alignment angle as functions
of halo mass (M), ellipticity (epsilon), distance (r) and velocity (v) and show
that the model, after tuning of three parameters, provides a good fit to the
numerical results. The parameters indicate a high degree of alignment along
anisotropic, collapsed filaments. The degree of alignment increases with M and
epsilon while it decreases with r and is independent of v. We note the
possibility of using the cluster-supercluster alignment effect as a
cosmological probe to constrain the slope of the initial power spectrum.
