Reactivity of CO on Ni4 cluster- effect of spin multiplicity and H doping-A DFT investigation.
Spectrochim Acta A Mol Biomol Spectrosc
; 204: 362-369, 2018 Nov 05.
Article
in En
| MEDLINE
| ID: mdl-29957415
ABSTRACT
We investigated the reactivity of carbon monoxide on tetrahedral Ni4 clusters at different spin multiplicity applying density functional theory calculations considering pure and hybrid functional. The stability of the clusters increases with the increasing spin multiplicity and doping hydrogen in Ni4 cluster. The adsorption or binding energy of CO on Ni4 cluster is thermodynamically feasible process at normal condition whereas dissociation is not feasible. Ab initio molecular orbital analysis shows the orbital overlaps are observed at bridging site, three fold sites, and tetra coordinated centre and formation of δ-bond in the cluster. In NBO analysis, CO binds strongly to the Ni4 cluster not only by two NiC bond (spd hybrid), but also donor-acceptor delocalization interactions, for example, σ type BD(CO)â¯ââ¯BD*(NiC) and BD(NiC)â¯ââ¯BD*(NiC/CO), two π-type BD(CO)â¯ââ¯LP*(Ni) and several diffuse RY*(C)â¯ââ¯LP(Ni) and π*(CO)â¯ââ¯LP(Ni) interactions. Singlet Ni4 cluster shows highest activation energy barrier, 3â¯eV. H-doped Ni4 cluster decreases dissociation barrier and favors CH bond formation.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Spectrochim Acta A Mol Biomol Spectrosc
Journal subject:
BIOLOGIA MOLECULAR
Year:
2018
Document type:
Article