Abstract book - Prof. Per Jensen, Ph.D. - Bergische Universität ...

Poster session, H22 135The Infrared Spectrum of 13 C 2 H 2 : Bending States up to v 4 + v 5 = 4Michel Herman 1 , Luciano Fusina 2 , Gianfranco Di Lonardo 2 , Adriana Predoi-Cross 31 Service de Chimie quantique et Photophysique, Université Libre de Bruxelles(U.L.B.), Belgium, mherman@ulb.ac.be.it;2 Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Italy,luciano.fusina@unibo.it, gianfranco.dilonardo@unibo.it3 Department of Physics and Astronomy, University of Lethbridge, Canada,adriana.predoicross@gmail.comHerman M.Fusina L.Di Lonardo G.Predoi-Cross A.The vibration rotation spectra of 13 C substituted acetylene, 13 C 2H 2, have been recordedin the region between 60 and 2700 cm −1 with an effective resolution ranging from 0.001to 0.006 cm −1 . In the FIR range, from 60 to 250 cm −1 , the Canadian Light Sourcesynchrotron facility was used (resolution = 0.001 cm −1 ). Between 400 and 800cm −1 the modified BOMEM FTIR instrument present in Ottawa was used (resolution =0.002 – 0.003 cm −1 ) . The spectra above 1000 cm -1 were recorded in Bologna at aresolution of 0.004 – 0.006 cm −1 . A total of about 9500 rovibrational transitions havebeen assigned to 101 bands involving the bending states up to v t = v 4 + v 5 = 4, allowingthe characterization of the ground state and of 33 vibrationally excited states. All thebands involving states up to v t = 3 have been analyzed simultaneously by adopting amodel Hamiltonian which takes into account the vibration and rotation l-typeresonances. The derived spectroscopic parameters reproduce the transitionwavenumbers with a RMS value of the order of the experimental uncertainty. Using thesame model larger discrepancies between observed and calculated values have beenobtained for transitions involving states with v t = 4. These could be satisfactorilyreproduced only adopting, in addition to the previously determined parameters whichwere constrained in the analysis, a set of effective constants for each vibrationalmanifold.