Title
The Reactions Of Cr(Co)(6), Fe(Co)(5), And Ni(Co)(4) With O-2 Yield Viable Oxo-Metal Carbonyls
Abstract
Transition metal complexes with terminal oxo and dioxygen ligands exist in metal oxidation reactions, and many are key intermediates in various catalytic and biological processes. The prototypical oxo-metal [(OC)(5)CrO, (OC)(4)FeO, and (OC)(3)NiO] and dioxygen-metal carbonyls [(OC)(5)CrOO, (OC)(4)FeOO, and (OC)(3)NiOO] are studied theoretically. All three oxo-metal carbonyls were found to have triplet ground states, with metal-oxo bond dissociation energies of 77 (CrO), 74 (FeO), and 51 (NiO) kcal/mol. Natural bond orbital and quantum theory of atoms in molecules analyses predict metal-oxo bond orders around 1.3. Their featured (MO, M=metal) vibrational frequencies all reflect very low IR intensities, suggesting Raman spectroscopy for experimental identification. The metal interactions with O-2 are much weaker [dissociation energies 13 (CrOO), 21 (FeOO), and 4 (NiOO) kcal/mol] for the dioxygen-metal carbonyls. The classic parent compounds Cr(CO)(6), Fe(CO)(5), and Ni(CO)(4) all exhibit thermodynamic instability in the presence of O-2, driven to displacement of CO to form CO2. The latter reactions are exothermic by 47 [Cr(CO)(6)], 46 [Fe(CO)(5)], and 35 [Ni(CO)(4)] kcal/mol. However, the barrier heights for the three reactions are very large, 51 (Cr), 39 (Fe), and 40 (Ni) kcal/mol. Thus, the parent metal carbonyls should be kinetically stable in the presence of oxygen. (c) 2014 Wiley Periodicals, Inc.
Year
DOI
Venue
2014
10.1002/jcc.23585
JOURNAL OF COMPUTATIONAL CHEMISTRY
Keywords
Field
DocType
metal carbonyls, oxo-metal carbonyls, dioxygen-metal carbonyls, DFT, bond dissociation energies
Metal carbonyl,Inorganic chemistry,Chemistry,Photochemistry,Bond-dissociation energy
Journal
Volume
Issue
ISSN
35
13
0192-8651
Citations 
PageRank 
References 
0
0.34
0
Authors
5
Name
Order
Citations
PageRank
Zhi Sun100.34
Henry F Schaefer2227.18
Yaoming Xie301.69
Yongdong Liu400.34
Rugang Zhong500.68