title: Isomeric transitions in size-selected methanol hexamers probed by OH-stretch spectroscopy.
abstract: We have measured the isomeric transition between the energetically lowest lying isomers of S6 and C2-symmetry of (CH3OH)6. The clusters are size-selected by deflection in collisions with He, and the isomers are identified by their infrared spectra of the OH-stretching vibration. The measurements are carried out at three source temperatures 253, 300 and 373 K which correspond to the cluster temperatures 93, 106 and 135 K. The latter ones are estimated by a relaxation model that accounts for the cluster formation and the energy released by the condensation. The transition takes place at a cluster temperature of about 102 K which is in agreement with the Molecular Dynamics simulation of such a transition at about 117 K using a realistic model potential.
authors.affiliation: Max-Planck-Institut für Dynamik und Selbstorganisation, Bunsenstrasse 10, 37073 Göttingen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Steinbach
authors.forename: M
authors.initials: M
authors.lastname: Fárník
authors.forename: I
authors.initials: I
authors.lastname: Ettischer
authors.forename: J
authors.initials: J
authors.lastname: Siebers
authors.forename: U
authors.initials: U
authors.lastname: Buck
mesh_terms: D003198:Computer Simulation; D007536:Isomerism; D046911:Macromolecular Substances / Q000737:chemistry; D000432:Methanol / Q000737:chemistry*; D008956:Models, Chemical; D044367:Phase Transition; D011789:Quantum Theory; D013055:Spectrophotometry, Infrared; D013696:Temperature
chemical_list: D046911:Macromolecular Substances; D000432:Methanol