Phys. Rev. Lett. 93, 250401 (2004) [4 pages]Roton-Rotation Coupling of Acetylene in 4HeReceived 15 April 2004; published 13 December 2004 Rotational absorption spectra of acetylene in superfluid 4He calculated using a path-integral correlation function approach are seen to result in an anomalously large distortion constant in addition to a reduced rotational constant, with values in excellent agreement with recent experiments. Semianalytic treatment of the dynamics with a combined correlated basis function-diffusion Monte Carlo method reveals that this anomalous behavior is due to strong coupling of the higher rotational states of the molecule with the roton and maxon excitations of 4He, and the associated divergence of the 4He density of states in this region. © 2004 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevLett.93.250401
DOI:
10.1103/PhysRevLett.93.250401
PACS:
05.30.Jp, 33.20.Bx, 33.20.Sn, 36.40.–c
|
