title: Spectroscopy of the Ã state of NO-alkane complexes (alkane = methane, ethane, propane, and n-butane).
abstract: We have recorded (1+1) resonance-enhanced multiphoton ionization spectra of complexes formed between NO and the alkanes: CH(4), C(2)H(6), C(3)H(8), and n-C(4)H(10). The spectra correspond to the Ã ← X̃ transition, which is a NO-localized 3s ← 2pπ* transition. In line with previous work, the spectrum for NO-CH(4) has well-defined structure, but this is only partially resolved for the other complexes. The spectra recorded in the NO(+)-alkane mass channels all show a slowly rising onset, followed by a sharp offset, which is associated with dissociation of NO-alkane, from which binding energies in the X̃ and Ã states are deduced. Beyond this sharp offset, there is a further rise in signal, which is attributed to fragmentation of higher complexes, NO-(alkane)(n). Analysis of these features allows binding energies for (NO-alkane)···alkane to be estimated, and these suggest that in the NO-(alkane)(2) complexes, the second alkane molecule is bound to the first, rather than to NO. Calculated structures for the 1:1 complexes are reported, as well as binding energies.
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Victor M
authors.initials: VM
authors.lastname: Tamé-Reyes
authors.forename: Adrian M
authors.initials: AM
authors.lastname: Gardner
authors.forename: Joe P
authors.initials: JP
authors.lastname: Harris
authors.forename: Jodie
authors.initials: J
authors.lastname: McDaniel
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Wright