Time-resolved vacuum-ultraviolet photoelectron spectroscopy of the Ã1Au state of acetylene
Abstract
Ultrafast time-resolved photoelectron spectra are reported for the vacuum-ultraviolet (VUV) photoionization of acetylene following excitation to the Ã1Au state via UV absorption at 200 nm. The excitation energy lies above the lowest dissociation threshold to C2H X̃2Σ+ + H, as well as above the threshold for adiabatic dissociation of the Ã1Au state to form C2H (Ã2Π) + H. The time-dependent mass spectra and photoelectron spectra provide insight into the intramolecular decay processes of the Ã1Au state. In addition, photoelectron spectra of the Ã1Au state with VUV light access both the X̃2Πu and Ã2Σg+ states of the ion, as well as the predicted, but previously unobserved, 1 2Πg state, which corresponds to a two-hole, one-particle configuration that lies in close proximity to the Ã2Σg+ state. The 1 2Πg state is split into 2A2 + 2B2 and 2Ag + 2Bg states in the cis and trans configurations, respectively. Electronic structure calculations, along with trajectory calculations, reproduce the principal features of the experimental data and confirm the assignment of the 1 2Πg state.
Article Details
Journal Info
The Journal of Chemical Physics
American Institute of Physics
Authors (31)
Weronika O. Razmus
Antonio Prlj
Ruđer Bošković Institute, Department of Physical Chemistry 2 , Bijenička 54, 10000 Zagreb,
Nathan A. Seifert
Department of Chemistry
Matteo Bonanomi
Dipartimento di Fisica
Carlo Callegari
Elettra–Sincrotrone Trieste S.C.p.A.
Miltcho Danailov
Piero Decleva
Dipartimento di Science Chimiche e Farmaceutiche
Alexander Demidovich
Elettra–Sincrotrone Trieste S.C.p.A.
Giovanni De Ninno
Elettra Sincrotrone Trieste 6 , I-34149 Trieste,
Michele Devetta
CNR–Istituto di Fotonica e Nanotecnologie (IFN)
Davide Faccialà
CNR–Istituto di Fotonica e Nanotecnologie (IFN)
Raimund Feifel
Department of Physics
Luca Giannessi
University of Southampton, Chemistry Department 1 , Southampton SO17 1BJ, Hants,
Tomislav Piteša
Ruđer Bošković Institute, Department of Physical Chemistry 2 , Bijenička 54, 10000 Zagreb,
Ivan Powis
Department of Chemistry, University of Nottingham 11 , Nottingham NG7 2RD,
Lorenzo Raimondi
Katharine L. Reid
Department of Chemistry, University of Nottingham 11 , Nottingham NG7 2RD,
Primož Rebernik Ribič
Elettra Sincrotrone Trieste 6 , I-34149 Trieste,
Carlo Spezzani
Elettra Sincrotrone Trieste 6 , I-34149 Trieste,
Richard J. Squibb
Department of Physics
James O. F. Thompson
Central Laser Facility, STFC Rutherford Appleton Laboratory 4 , Didcot, Oxfordshire OX11 0QX,
Oksana Plekan
Elettra–Sincrotrone Trieste S.C.p.A.
Caterina Vozzi
CNR–Istituto di Fotonica e Nanotecnologie (IFN)
Emily M. Warne
Chemistry Research Laboratory, Department of Chemistry
Marco Zangrando
Elettra–Sincrotrone Trieste S.C.p.A.
Kevin C. Prince
Elettra–Sincrotrone Trieste S.C.p.A.
Michele Di Fraia
Elettra–Sincrotrone Trieste S.C.p.A.
David M. P. Holland
Daresbury Laboratory
Russell S. Minns
School of Chemistry and Chemical Engineering
Nađa Došlić
Department of Physical Chemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
Stephen T. Pratt
Chemical Sciences and Engineering Division, Argonne National Laboratory 15 , Lemont, Illinois 60439,