ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The rotationally resolved infrared spectra of single SF6 molecules embedded in large 3He droplets have been studied as a function of mean sizes between N¯3=2×103 and 105 atoms by the cluster beam depletion technique. The observed frequency shifts and line broadening of the dopant spectra are interpreted in terms of the small impurity of about 30–50 4He atoms, which because of their lower zero point energy completely surround the SF6 molecule. For the largest droplets, the observed rotational structure is similar to that observed in pure 4He droplets but the rotational temperature as determined from the relative line intensities is Trot=0.15(1) K, which is about a factor 2.5 lower than in pure 4He droplets. The lower temperature is expected on the basis of the lower heat of evaporation of the 3He atoms on the outside of the droplet. Mixed 3He/4He droplets produced by increasing the 4He concentration in the source gas to 1.2 and 4% of the 3He were found to have temperatures between that for the almost pure 3He droplets and that for pure 4He droplets. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.479110
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