dc.contributor.author
Uranga-Piña, L.
dc.contributor.author
Tremblay, J. C.
dc.date.accessioned
2018-06-08T03:57:18Z
dc.date.available
2014-09-12T08:20:10.219Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/16286
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-20469
dc.description.abstract
We investigate the effect of inter-mode coupling on the vibrational relaxation
dynamics of molecules in weak dissipative environments. The simulations are
performed within the reduced density matrix formalism in the Markovian regime,
assuming a Lindblad form for the system-bath interaction. The prototypical
two-dimensional model system representing two CO molecules approaching a
Cu(100) surface is adapted from an ab initio potential, while the diatom-
diatom vibrational coupling strength is systematically varied. In the weak
system-bath coupling limit and at low temperatures, only first order non-
adiabatic uni-modal coupling terms contribute to surface-mediated vibrational
relaxation. Since dissipative dynamics is non-unitary, the choice of
representation will affect the evolution of the reduced density matrix. Two
alternative representations for computing the relaxation rates and the
associated operators are thus compared: the fully coupled spectral basis, and
a factorizable ansatz. The former is well-established and serves as a
benchmark for the solution of Liouville-von Neumann equation. In the latter, a
contracted grid basis of potential-optimized discrete variable representation
is tailored to incorporate most of the inter-mode coupling, while the Lindblad
operators are represented as tensor products of one-dimensional operators, for
consistency. This procedure results in a marked reduction of the grid size and
in a much more advantageous scaling of the computational cost with respect to
the increase of the dimensionality of the system. The factorizable method is
found to provide an accurate description of the dissipative quantum dynamics
of the model system, specifically of the time evolution of the state
populations and of the probability density distribution of the molecular wave
packet. The influence of intra-molecular vibrational energy redistribution
appears to be properly taken into account by the new model on the whole range
of coupling strengths. It demontrates that most of the mode mixing during
relaxation is due to the potential part of the Hamiltonian and not to the
coupling among relaxation operators
en
dc.rights.uri
http://publishing.aip.org/authors/web-posting-guidelines
dc.subject.ddc
500 Naturwissenschaften und Mathematik::540 Chemie
dc.subject.ddc
500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::572 Biochemie
dc.title
Relaxation dynamics in quantum dissipative systems
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation
J. Chem. Phys. - 141 (2014), 7, Artikel Nr. 074703
dc.title.subtitle
The microscopic effect of intramolecular vibrational energy redistribution
dcterms.bibliographicCitation.doi
10.1063/1.4892376
dcterms.bibliographicCitation.url
http://dx.doi.org/10.1063/1.4892376
refubium.affiliation
Biologie, Chemie, Pharmazie
de
refubium.funding
OpenAccess Publikation in Allianzlizenz
refubium.mycore.fudocsId
FUDOCS_document_000000020955
refubium.resourceType.isindependentpub
no
refubium.mycore.derivateId
FUDOCS_derivate_000000003907
dcterms.accessRights.openaire
open access
dcterms.isPartOf.issn
0021-9606