Polarizabilities of Sc and Ti atoms and dispersion coefficients for their interaction with helium atoms

The dynamic scalar and tensor polarizabilities of Sc and Ti are computed with time-dependent density functional theory. These polarizabilities are used to compute the isotropic and anisotropic dispersion interactions in ScHe and TiHe. We find C6,0(ScHe)=30.00 , C6,2(ScHe)=-1.63 , C6,0(TiHe)=28.40 , and C6,2(TiHe)=-0.90 (Eha06) . We show that an estimate of the dispersion anisotropy based on static polarizabilities results in an overestimation by a factor of 2.Physic