  We report calculations of Born-Oppenheimer potential energy curves of the
chromium-rubidium heteronuclear molecule 52Cr-87Rb, and the long-range
dispersion coefficient for the interaction between ground state Cr and Rb
atoms. Our calculated van der Waals coefficient (C6=1770 a.u.) has an expected
error of 3%. The ground state 6Sigma+ molecule at its equilibrium separation
has a permanent electric dipole moment of de (Re=3.34 A) = 2.90 D. We
investigate the hyperfine and dipolar collisions between trapped Cr and Rb
atoms, finding elastic to inelastic cross section ratio of 100-1000.
