Kontsevich's graph complex, GRT, and the deformation complex of the   sheaf of polyvector fields
  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. 
Vasily Dolgushev, Christopher L. Rogers, and Thomas Willwacher
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