Published in

American Chemical Society, The Journal of Physical Chemistry A, 5(117), p. 814-820, 2013

DOI: 10.1021/jp3117616

Links

Tools

Export citation

Search in Google Scholar

Experimental and Computational Study of the Gas-Phase Reaction of O(1D) Atoms with VF5

This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
  • Must obtain written permission from Editor
  • Must not violate ACS ethical Guidelines
Orange circle
Postprint: archiving restricted
  • Must obtain written permission from Editor
  • Must not violate ACS ethical Guidelines
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

The reactions of O((1)D) atoms with VF(5) at room temperature have been studied by time-resolved laser magnetic resonance at the buffer gas (SF(6)) pressure of 6 Torr. The O((1)D) atoms were produced by the photodissociation of ozone using an excimer laser (KrF, 248 nm). By monitoring the kinetics of FO radical formation, the bimolecular rate constant of O((1)D) consumption in collisions with VF(5) has been determined to be k(VF(5)) = (7.5±2.2)×10(-11) cm(3)s(-1). The branching ratio for the channel producing FO radicals (k(8a)) has been found to be k(8a)/k(VF(5)) = 0.11±0.02. Quantum chemical calculations at the CCSD(T)/CBS level of theory give evidence that the reactions O((1)D) with VF(5) proceed via the VF(4)OF intermediate. The enthalpy of the reaction leading to this intermediate formation was calculated to be -245.8 kJ/mol. In qualitative agreement with the experimental results, the reaction channel O((1)D) + VF(5) → FO + VF(4) (8a) turned out to be 72.9 kJ/mol energetically more favorable than the channel O((1)D) + VF(5) → F + OVF(4) (8b). The dissociation enthalpy of the OVF(4) radical was calculated to be very low (18.1 kJ/mol), hence the decay of OVF(4) to F + OVF(3) should proceed very fast. The molecular channel O((1)D) + VF(5) → F(2)+VF(3)O, though being most favorable thermodynamically, is kinetically unimportant.