Effect of exchange on the rotational dynamics of doped helium clusters

We study the importance of exchange effects on the rotational dynamics of small doped helium clusters by comparing the result of path integral Monte Carlo simulations for Boltzmann and Bose-Einstein statistics. The variation of the effective rotational constant with cluster size and temperature is discussed for both statistics. We rationalize the discrepancy between the Boltzmann and the Bose-Einstein results in terms of the superfluid response of the complex defined in the molecule frame of the rotating impurity.