  We generalize Kontsevich's construction of L-infinity derivations of
polyvector fields from the affine space to an arbitrary smooth algebraic
variety. More precisely, we construct a map (in the homotopy category) from
Kontsevich's graph complex to the deformation complex of the sheaf of
polyvector fields on a smooth algebraic variety. We show that the action of
Deligne-Drinfeld elements of the Grothendieck-Teichmueller Lie algebra on the
cohomology of the sheaf of polyvector fields coincides with the action of odd
components of the Chern character. Using this result, we deduce that the A-hat
genus in the Calaque-Van den Bergh formula arXiv:0708.2725 for the isomorphism
between harmonic and Hochschild structures can be replaced by a generalized
A-hat genus.
