title: Infrared spectra in the 3 μm region of ethane and ethane clusters in helium droplets.
abstract: Ethane and ethane clusters (N ≈ 10(2)-10(4)) were studied inside helium droplets with infrared laser spectroscopy. The spectra were measured in the 2880-3000 cm(-1) range, which covers the ν5, ν(8+11), and ν7 vibrational bands of ethane. Partially resolved rotational fine structure in the spectrum of the monomer reveals solvent-induced band origin blue shifts that are each approximately 1 cm(-1). The effective B(He) and A(He) rotational constants were found to be reduced by 52% and 16% in comparison to their gas phase values, respectively. Spectra of the clusters show the same three bands shifted toward low frequency by approximately 10 cm(-1) because of intermolecular interactions in the clusters. The spectra of the ethane clusters are dominated by the ν7 band, whereas the relative intensities of the ν5 and ν(8+11) bands are about a factor of 5 weaker than for single molecules or for solid ethane, the spectrum of which is also reported here.
authors.affiliation: Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Gomez
authors.forename: Russell
authors.initials: R
authors.lastname: Sliter
authors.forename: Dmitry
authors.initials: D
authors.lastname: Skvortsov
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Hoshina
authors.forename: Gary E
authors.initials: GE
authors.lastname: Douberly
authors.forename: Andrey F
authors.initials: AF
authors.lastname: Vilesov