dc.creator Gillies, C. W. en_US dc.creator Gillies, J. Z. en_US dc.date.accessioned 2006-06-15T19:06:01Z dc.date.available 2006-06-15T19:06:01Z dc.date.issued 1998 en_US dc.identifier 1998-RJ-11 en_US dc.identifier.uri http://hdl.handle.net/1811/18987 dc.description Author Institution: Department of Chemistry, Rensselaer Polytechnic Institute; Department of Chemistry, Siena College en_US dc.description.abstract The rotational spectrum of the oblate asymmetric top van der Waals trimer, $Ar_{2}$-ketene, was obtained with a pulsed-beam Fourier-transform microwave spectrometer. Two tunnelling states arising from internal rotation of ketene were assigned for $Ar_{2}CH_{2}CO$ and $Ar_{2}CD_{2}CO$. The least squares fit of the observed $\mu_{b}$ and $\mu_{c}$-type transitions of the ground state normal isotopomer to a semirigid Watson Hamiltonian gave rotational constants of $A = 1652.28376(17)MHz. B = 1484.42510(16)MHz$ and $C = 914.02182(37)MHz$. Electric dipole moment components of $\mu_{b} = 0.175(18)D$ and $\mu_{c} = 1.343(3)D$ were calculated from Stark shift measurements of the ground state normal isotopomer. The spectral data are consistent with a trimer structure in which the CCO axis of ketene is perpendicular to the Ar-Ar axis. Least squares fits of the moments of inertia of the two isotopomers gave an Ar-Ar separation of 1.916(2){AA}, a ketene center of mass to the Ar-Ar bisector of 3.039(5){\AA} and an angle of $99.5(1.5)^{\circ}$ between the methylene carbon, center of mass of ketene and the point at the bisector of the Ar-Ar separation. en_US dc.format.extent 119202 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title THE VAN DER WAALS TRIMER, $AR_{2}$KETENE en_US dc.type article en_US
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