RT info:eu-repo/semantics/article
T1 Structural and Electronic Rearrangements in Fe2S2, Fe3S4, and Fe4S4 Atomic Clusters under the Attack of NO, CO, and O2
A1 Amitouche, Fadila
A1 Saad, Farida
A1 Tazibt, Slimane
A1 Bouarab, Said
A1 Vega Hierro, Andrés
K1 Iron
K1 Molecular structure
K1 22 Física
AB We report results, based on density functional theory–generalized gradient approximation calculations, that shed light on how NO, CO, and O2 interact with Fe2S2, Fe3S4, and Fe4S4 clusters and how they modify their structural and electronic properties. The interest in these small iron sulfide clusters comes from the fact that they are at the protein cores and that elucidating fundamental aspects of their interaction with those light molecules which are known to modify their functionality may help in understanding complex behaviors in biological systems. CO and NO are found to bind molecularly, leading to moderate relaxations in the clusters, but nevertheless to changes in the spin-polarized electronic structure and related properties. In contrast, dissociative chemisorption of O2 is much more stable than molecular adsorption, giving rise to significant structural distortions, particularly in Fe4S4 that splits into two Fe2S2 subclusters. As a consequence, oxygen tends to strongly reduce the spin polarization in Fe and to weaken the Fe–Fe interaction inducing antiparallel couplings that, in the case of Fe4S4, clearly arise from indirect Fe–Fe exchange coupling mediated by O. The three molecules (particularly CO) enhance the stability of the iron–sulfur clusters. This increase is noticeably more pronounced for Fe2S2 than for the other iron–sulfur clusters of different compositions, a result that correlates with the fact that in recent experiments of CO reaction with FemSm (m = 1–4), the Fe2S2CO product results as a prominent one.
PB American Chemical Society
SN 1520-5215
YR 2019
FD 2019
LK http://uvadoc.uva.es/handle/10324/42625
UL http://uvadoc.uva.es/handle/10324/42625
LA eng
NO Journal of Physical Chemistry A, 2019, 123, 51, 10919–10929
NO Producción Científica
DS UVaDOC
RD 23-nov-2024