Unveiling the Nature of Binding Interactions of Acetylene and Ethylene with Triangular Coinage Metal Clusters: A DFT Computational Study
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Organometallics
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Density functional theory calculations have been employed to study the molecular and electronic structures, stabilities, and bonding features of a series of metal clusters with the general formulas [c-M(3)L(n)](+) and [c-M(3)(mu(2)-H)(3)L(n)] (M = Cu, Ag, Au, L = ethylene, acetylene; n = 1-3) in their singlet ground states. The upright or in-plane orientation adopted by the eta(2)-coordinated unsaturated hydrocarbon ligands L in the [c-M(3)L(n)](+) and [c-M(3)(mu(2)-H)(3)L(n)] complexes respectively is strongly related to the electrophilicity index, omega, of the respective electrophilic [c-M(3)L(n-1)](+) and [c-M(3)(mu(2)-H)(3)-L(n-1)] fragments. We found that for to omega > 7 eV the unsaturated ligands adopt the upright orientation, while for omega < 2.95 eV the in-plane orientation is adopted. The bending back of the H atoms of acetylene and the pyramidalization of the carbon atoms of ethylene upon coordination of ligands L to the metal centers are due to favorable n(M) -> pi*(L) and pi(L) -> n(M) hyperconjugative interactions. Charge (CDA) and energy decomposition analysis (EDA) indicate that acetylene/ethylene are more strongly bound to the "naked" rather than to the hydrido-bridged triangular noble metal clusters, while the M-C(2)H(2)/C(2)H(4) binding interactions are predicted to be predominantly electrostatic rather than covalent. On the basis of the EDA analysis the contribution of pi-back-bonding, and even delta-back-bonding for the acetylene complexes, to the covalent interactions are far more significant than sigma-bonding in [c-M(3)L(n)](+) clusters, while the opposite holds true for the [c-M(3)(mu(2)-H)(3)L(n)] clusters.
Περιγραφή
Λέξεις-κλειδιά
effective core potentials, regular 2-component hamiltonians, density-functional theory, diatomic silver cations, transition-state method, molecular calculations, copper(i) ethylene, ethene complexes, aromatic-hydrocarbons, theoretical chemistry
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000273618600011
http://pubs.acs.org/doi/abs/10.1021/om900781j
http://pubs.acs.org/doi/abs/10.1021/om900781j
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας