Multireference theoretical investigation on selectivity of the bond fissions in photodissociation of acetyl cyanide

Journal Article · Fri Dec 28 04:00:00 EST 2007 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.2814169· OSTI ID:21024627

Hongyan, Xiao; Yajun, Liu; Weihai, Fang ^[1]

---

1. College of Chemistry, Beijing Normal University, Beijing 100875 (China)

The selectivity of the C-CH{sub 3} and C-CN bond fissions upon excitation of acetyl cyanide at 193 nm has been investigated at the theoretical level of multistate complete active space self-consistent field second order perturbation. The calculated results indicated that the initially excited S{sub 3} state relaxes to S{sub 2} via ultrafast internal conversion. The S{sub 2} state could dissociate via two pathways. One, adiabatically dissociates to CH{sub 3}CO(X-tilde)+CN(A-tilde). The other one internally converts to S{sub 1} before S{sub 1} intersystem crossing to T{sub 1}. The T{sub 1} state subsequently dissociates to two groups of products: CH{sub 3}(X-tilde)+OCCN(X-tilde) and CH{sub 3}CO(X-tilde)+CN(X-tilde). The experimentally observed preference branching of CN elimination over CH{sub 3} one and bond selectivity are the results of the competition between the adiabatic and nonadiabatic dynamics of the S{sub 2} state.

• OSTI ID: 21024627
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 24 Vol. 127; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACETONITRILE
BRANCHING RATIO
CARBON NITRIDES
CHEMICAL BONDS
CYANIDES
DISSOCIATION
EXCITED STATES
INTERNAL CONVERSION
PERTURBATION THEORY
PHOTOCHEMISTRY
PHOTOLYSIS
PHOTON-MOLECULE COLLISIONS
REACTION KINETICS
SELF-CONSISTENT FIELD