The University of Southampton
University of Southampton Institutional Repository

The chemiionization reactions Ce+O and Ce+O2: assignment of the observed chemielectron bands

The chemiionization reactions Ce+O and Ce+O2: assignment of the observed chemielectron bands
The chemiionization reactions Ce+O and Ce+O2: assignment of the observed chemielectron bands
Multiconfigurational quantum chemical methods (CASSCF/CASPT2) have been used to study the chemiionization reactions Ce + O CeO+ + e- and Ce + O2 CeO + e-. Selected spectroscopic constants for CeOn and CeO (n = 1, 2), as well as reaction enthalpies of the chemiionization reactions of interest, have been computed and compared with experimental values. In contrast to the lanthanum case, for both Ce + O2(X3) and Ce + O2( a1g), the Ce + O2 CeO + e- reaction is shown to be exothermic, and thus, contributes to the experimental chemielectron spectra. The apparent discrepancy between the computed reaction enthalpies and the high kinetic energy offset values measured in the chemielectron spectra is rationalized by arguing that chemielectrons are produced mainly via two sequential reactions (Ce + O2 CeO + O, followed by Ce + O CeO+ + e-) as in the case of lanthanum. For Ce + O2 (a1g), a chemielectron band with higher kinetic energy than that recorded for Ce + O2( X3) is obtained. This is attributed to production of O( 1D) from the reaction Ce + O2( a1g) CeO + O( 1D), followed by chemiionization via the reaction Ce + O( 1D) CeO+ + e-. Accurate potential energy curves for the ground and a number of excited states of CeO and CeO+ have been computed, and a mechanism for the chemiionization reactions investigated experimentally was proposed.
cerium oxides, multiconfigurational methods, chemiionization reactions, spin-orbit coupling
0020-7608
2068-2079
Todorova, Tanya K.
de270f0a-1abc-4d7c-97f4-58a5d2860b23
Infante, Ivan
69c5436a-4746-4e1a-b9c9-65b06af14f03
Gagliardi, Laura
7289d411-f5b8-4b27-ae02-4eac1ee375b3
Dyke, John M.
46393b45-6694-46f3-af20-d7369d26199f
Todorova, Tanya K.
de270f0a-1abc-4d7c-97f4-58a5d2860b23
Infante, Ivan
69c5436a-4746-4e1a-b9c9-65b06af14f03
Gagliardi, Laura
7289d411-f5b8-4b27-ae02-4eac1ee375b3
Dyke, John M.
46393b45-6694-46f3-af20-d7369d26199f

Todorova, Tanya K., Infante, Ivan, Gagliardi, Laura and Dyke, John M. (2009) The chemiionization reactions Ce+O and Ce+O2: assignment of the observed chemielectron bands. International Journal of Quantum Chemistry, 109 (10), 2068-2079. (doi:10.1002/qua.22058).

Record type: Article

Abstract

Multiconfigurational quantum chemical methods (CASSCF/CASPT2) have been used to study the chemiionization reactions Ce + O CeO+ + e- and Ce + O2 CeO + e-. Selected spectroscopic constants for CeOn and CeO (n = 1, 2), as well as reaction enthalpies of the chemiionization reactions of interest, have been computed and compared with experimental values. In contrast to the lanthanum case, for both Ce + O2(X3) and Ce + O2( a1g), the Ce + O2 CeO + e- reaction is shown to be exothermic, and thus, contributes to the experimental chemielectron spectra. The apparent discrepancy between the computed reaction enthalpies and the high kinetic energy offset values measured in the chemielectron spectra is rationalized by arguing that chemielectrons are produced mainly via two sequential reactions (Ce + O2 CeO + O, followed by Ce + O CeO+ + e-) as in the case of lanthanum. For Ce + O2 (a1g), a chemielectron band with higher kinetic energy than that recorded for Ce + O2( X3) is obtained. This is attributed to production of O( 1D) from the reaction Ce + O2( a1g) CeO + O( 1D), followed by chemiionization via the reaction Ce + O( 1D) CeO+ + e-. Accurate potential energy curves for the ground and a number of excited states of CeO and CeO+ have been computed, and a mechanism for the chemiionization reactions investigated experimentally was proposed.

Text
CeODraftSept08.doc - Other
Download (732kB)

More information

Published date: March 2009
Keywords: cerium oxides, multiconfigurational methods, chemiionization reactions, spin-orbit coupling

Identifiers

Local EPrints ID: 147169
URI: http://eprints.soton.ac.uk/id/eprint/147169
ISSN: 0020-7608
PURE UUID: d36dc90e-36bf-4f19-952e-01caddf7db87
ORCID for John M. Dyke: ORCID iD orcid.org/0000-0002-9808-303X

Catalogue record

Date deposited: 23 Apr 2010 11:36
Last modified: 14 Mar 2024 02:33

Export record

Altmetrics

Contributors

Author: Tanya K. Todorova
Author: Ivan Infante
Author: Laura Gagliardi
Author: John M. Dyke ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×