  We present a systematic study of interaction induced dipole electric
properties of all molecular dimers in the S66 set, relying on
CCSD(T)-F12b/aug-cc-pVDZ-F12 as reference level of theory. For field strengths
up to $\approx$5 GV m$^{-1}$ the interaction induced electric response beyond
second order is found to be insignificant. Large interaction dipole moments
(i.e. dipole moment changes due to van der Waals binding) are observed in the
case of hydrogen bonding oriented along the intermolecular axis, and mostly
small interaction dipole moments are found in dimers bonded by $\pi$-stacking
or London dispersion. The interaction polarizabilities (i.e. polarizability
changes due to van der Waals binding) were generally found to be small but
always with a positive-valued principal component approximately aligned with
the intermolecular axis, and two other negative-valued components. Energy
decompositions according to symmetry adapted perturbation theory
(SAPT0/jun-cc-pVDZ) suggest that electrostatics dominates the interaction
dipole moment. First-order SAPT0 decompositions into monomer-resolved
contributions establish a quantitative link between electric properties of
monomers and dimers. Using the aug-cc-pVQZ basis and non-empirical PBE
semilocal exchange-correlation kernels, we also assess how density functional
approximations in the nonlocal exchange and correlation parts affect the
predictive accuracy: While dRPA@PBE0 based predictions are in excellent overall
agreement with coupled cluster results, the computationally more affordable
LC-$\omega$PBE0-D3 level of theory also yields reliable results with relative
errors below 5\%. PBE alone, even when dispersion corrected, produces larger
errors in interaction dipole moments and polarizabilities.

Chemical Physics