skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The à 1Au state of acetylene: ungerade vibrational levels in the region 45,800–46,550 cm-1

Abstract

The ungerade vibrational levels of the à 1Au (S1-trans) state of C2H2 lying in the region 45,800-46,550 cm-1 have been assigned from IR-UV double resonance spectra. The aim has been to classify the complete manifold of S1-trans levels in this region, so as to facilitate the assignment of the bands of S1-cis C2H2. The rotational structure is complicated because of the overlapping of vibrational polyads with different Coriolis and Darling–Dennison parameters, but assignments have been possible with the help of predictions based on the properties of polyads at lower energy. An important result is that the analysis of the (1141, 1161) polyad determines the anharmonicity constants x14 and x16, which will be needed to proceed to higher energies. Some regions of impressive complexity occur. Among these is the band given by the 3361, K=1 state at 45,945 cm-1, where a three-level interaction within the S1 state is confused by triplet perturbations. Several probable S1-cis states have been observed, including cis-62, K=1; this vibrational level appears to show a K-staggering, of the type that arises when quantum mechanical tunnelling through the barrier to cis-trans isomerization is possible. The total number of identified cis vibrational states is now 6 out of anmore » expected 10 up to the energies discussed in this paper.« less

Authors:
 [1];  [1];  [2];  [1];  [1];  [1]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Chemistry
  2. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, (Taiwan) ; Univ. of British Columbia, Vancouver, BC (Canada). Dept. of Chemistry
Publication Date:
Research Org.:
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1169176
Grant/Contract Number:  
FG02-87ER13671
Resource Type:
Accepted Manuscript
Journal Name:
Molecular Physics
Additional Journal Information:
Journal Volume: 110; Journal Issue: 21-22; Journal ID: ISSN 0026-8976
Publisher:
Taylor & Francis
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; acetylene; cis-trans isomerization; double resonance; spectroscopy; perturbations

Citation Formats

Baraban, Joshua H., Changala, P. Bryan, Merer, Anthony J., Steeves, Adam H., Bechtel, Hans A., and Field, Robert W. The à 1Au state of acetylene: ungerade vibrational levels in the region 45,800–46,550 cm-1. United States: N. p., 2012. Web. doi:10.1080/00268976.2012.706329.
Baraban, Joshua H., Changala, P. Bryan, Merer, Anthony J., Steeves, Adam H., Bechtel, Hans A., & Field, Robert W. The à 1Au state of acetylene: ungerade vibrational levels in the region 45,800–46,550 cm-1. United States. doi:10.1080/00268976.2012.706329.
Baraban, Joshua H., Changala, P. Bryan, Merer, Anthony J., Steeves, Adam H., Bechtel, Hans A., and Field, Robert W. Tue . "The à 1Au state of acetylene: ungerade vibrational levels in the region 45,800–46,550 cm-1". United States. doi:10.1080/00268976.2012.706329. https://www.osti.gov/servlets/purl/1169176.
@article{osti_1169176,
title = {The à 1Au state of acetylene: ungerade vibrational levels in the region 45,800–46,550 cm-1},
author = {Baraban, Joshua H. and Changala, P. Bryan and Merer, Anthony J. and Steeves, Adam H. and Bechtel, Hans A. and Field, Robert W.},
abstractNote = {The ungerade vibrational levels of the à 1Au (S1-trans) state of C2H2 lying in the region 45,800-46,550 cm-1 have been assigned from IR-UV double resonance spectra. The aim has been to classify the complete manifold of S1-trans levels in this region, so as to facilitate the assignment of the bands of S1-cis C2H2. The rotational structure is complicated because of the overlapping of vibrational polyads with different Coriolis and Darling–Dennison parameters, but assignments have been possible with the help of predictions based on the properties of polyads at lower energy. An important result is that the analysis of the (1141, 1161) polyad determines the anharmonicity constants x14 and x16, which will be needed to proceed to higher energies. Some regions of impressive complexity occur. Among these is the band given by the 3361, K=1 state at 45,945 cm-1, where a three-level interaction within the S1 state is confused by triplet perturbations. Several probable S1-cis states have been observed, including cis-62, K=1; this vibrational level appears to show a K-staggering, of the type that arises when quantum mechanical tunnelling through the barrier to cis-trans isomerization is possible. The total number of identified cis vibrational states is now 6 out of an expected 10 up to the energies discussed in this paper.},
doi = {10.1080/00268976.2012.706329},
journal = {Molecular Physics},
number = 21-22,
volume = 110,
place = {United States},
year = {2012},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 20 works
Citation information provided by
Web of Science

Figures / Tables:

Table 1 Table 1: C2H2, band-by-band analyses of the ungerade states in the 45800 – 46500 cm−1 region. Rotational constants (cm−1) are from least squares fittings where a r.m.s. error is given. q is the same as ½(B−C) for K=1 states, and is the coefficient of J2(J+1)2 in the asymmetry splitting ofmore » K=2 states; a positive value of q means e levels above $f$. D terms are needed where b-axis Coriolis coupling distorts the rotational structure of a state; these D constants do not represent true centrifugal distortion.« less

Save / Share:

Works referenced in this record:

The Bent Excited State of Acetylene
journal, June 1952


Analysis of the Near Ultraviolet Absorption Spectrum of Acetylene
journal, May 1954

  • Innes, K. Keith
  • The Journal of Chemical Physics, Vol. 22, Issue 5
  • DOI: 10.1063/1.1740204

Stationary points on the S 1 potential energy surface of C 2 H 2
journal, July 1994

  • Stanton, John F.; Huang, Chang‐Ming; Szalay, Péter G.
  • The Journal of Chemical Physics, Vol. 101, Issue 1
  • DOI: 10.1063/1.468142

Ab initio MO studies on the photodissociation of C2H2 from the S1 (1Au) state. Non-adiabatic effects and S-T interaction
journal, December 1996


Ab initio MO studies on the photodissociation of C2H2 from the S1(1Au) state. II. Mechanism involving triplet states
journal, July 1997


Excited states of acetylene: a CASPT2 study
journal, November 1998

  • Malsch, Karsten; Rebentisch, Rupert; Swiderek, Petra
  • Theoretical Chemistry Accounts: Theory, Computation, and Modeling (Theoretica Chimica Acta), Vol. 100, Issue 1-4
  • DOI: 10.1007/s002140050377

The valence-excited states T1–T4 and S1–S2 of acetylene: A high-level MR-CISD and MR-AQCC investigation of stationary points, potential energy surfaces, and surface crossings
journal, January 2003

  • Ventura, Elizete; Dallos, Michal; Lischka, Hans
  • The Journal of Chemical Physics, Vol. 118, Issue 4
  • DOI: 10.1063/1.1532312

Conical intersections and strong nonadiabatic coupling effects in singlet-excited acetylene: An ab initio quantum dynamical study
journal, January 2008


Stretch-bend combination polyads in the Ã1Au state of acetylene, C2H2
journal, August 2009

  • Steeves, Adam H.; Bechtel, Hans A.; Merer, Anthony J.
  • Journal of Molecular Spectroscopy, Vol. 256, Issue 2
  • DOI: 10.1016/j.jms.2009.05.005

Cis-trans isomerization in the S 1 state of acetylene: Identification of cis-well vibrational levels
journal, June 2011

  • Merer, Anthony J.; Steeves, Adam H.; Baraban, Joshua H.
  • The Journal of Chemical Physics, Vol. 134, Issue 24
  • DOI: 10.1063/1.3599091

Reduced dimension discrete variable representation study of cis–trans isomerization in the S 1 state of C 2 H 2
journal, June 2011

  • Baraban, J. H.; Beck, A. R.; Steeves, A. H.
  • The Journal of Chemical Physics, Vol. 134, Issue 24
  • DOI: 10.1063/1.3570823

IR−UV Double Resonance Spectroscopy of Acetylene in the à 1 A u n ν 3 ‘+ν 4 ‘ and n ν 3 ‘+ν 6 ‘ ( n = 2, 3) Ungerade Vibrational States
journal, November 2000

  • Mizoguchi, Miwako; Yamakita, Nami; Tsuchiya, Soji
  • The Journal of Physical Chemistry A, Vol. 104, Issue 45
  • DOI: 10.1021/jp001215y

The direct observation, assignment, and partial deperturbation of the ν 4 and ν 6 vibrational fundamentals in A ̃  1 A u acetylene (C 2 H 2 )
journal, February 1993

  • Utz, A. L.; Tobiason, J. D.; Carrasquillo M., E.
  • The Journal of Chemical Physics, Vol. 98, Issue 4
  • DOI: 10.1063/1.464156

Darling–Dennison resonance and Coriolis coupling in the bending overtones of the ÃAu1 state of acetylene, C2H2
journal, August 2008

  • Merer, Anthony J.; Yamakita, Nami; Tsuchiya, Soji
  • The Journal of Chemical Physics, Vol. 129, Issue 5
  • DOI: 10.1063/1.2939246

The band system of acetylene
journal, September 1982


The direct observation, assignment, and partial deperturbation of ν 5 and ν 35 in A ̃  1 A u acetylene (C 2 H 2 )
journal, July 1993

  • Tobiason, J. D.; Utz, A. L.; Crim, F. F.
  • The Journal of Chemical Physics, Vol. 99, Issue 2
  • DOI: 10.1063/1.465357

Spectroscopic constants for the 2.5 and 3.0 μm bands of acetylene
journal, June 1990


Extended permutation-inversion groups for simultaneous treatment of the rovibronic states of trans-acetylene, cis-acetylene, and vinylidene
journal, May 2011


    Works referencing / citing this record:

    Probing the predissociated levels of the S 1 state of acetylene via H-atom fluorescence and photofragment fluorescence action spectroscopy
    journal, November 2018

    • Jiang, Jun; Saladrigas, Catherine A.; Erickson, Trevor J.
    • The Journal of Chemical Physics, Vol. 149, Issue 17
    • DOI: 10.1063/1.5045046