Metal—metal and metal—ligand bond strengths in metal carbonyl clusters

Kinetics and Mechanism of Reversible Oxidative Addition of Hydrogen across the Metal−Metal Bond of (μ-H)2Ru3(CO)8(μ-P(t-Bu)2)2. Steric Promotion of Metal−Metal Bond Cleavage But a CO Dissociative Mechanism

“…The longer unbridged Ru−Ru bond for the former (3.046 Å vs 2.9464 Å) is structural evidence for the weakening of this bond, presumably due to steric interactions. Using the bond length/bond energy relationship proposed for Ru 3 (CO) 12 , the corresponding unbridged Ru−Ru bond energies for (μ-H) 2 Ru 3 (CO) 8 (μ-PR 2 ) 2 , R = t -Bu and Ph, are 57 and 67 kJ/mol, respectively (cf. 78 kJ/mol for Ru 3 (CO) 12 ).…”

Triply Carbonyl-Bridged Ni2(CO)5Featuring Triple Three-Center Two-Electron Ni—C–Ni Bonds Instead of Ni≡Ni Triple Bond

“…Transition metal (TM) carbonyl complexes are ubiquitous in modern organometallic chemistry; their synthesis, characterization, and application have been fundamental constituents of extensively experimental and theoretical research, especially for the metal–metal interaction in these complexes. , The inherent essence of metal–metal bonding lies at the heart of the generalized understanding and specific applications in the fields of catalysis and the synthesis of metallic materials. − Mononuclear carbonyl complexes serve as a model compound for the 18-electron rule. However, the hypothetical existence of a direct or even multiple metal–metal bonds based on the 18-electron rule and the abnormally short metal–metal bond length remains a matter of discussion for some binuclear or multinuclear TM compounds supported by the bridging CO ligands in terms of Fe 2 (CO) 9 especially.…”

Infrared Photodissociation Spectroscopy of Mass-Selected Heteronuclear Iron–Copper Carbonyl Cluster Anions in the Gas Phase

“…Transition metal–carbonyl complexes are of great importance in inorganic and organometallic chemistry. − They are prototypical examples of metal–metal and metal–ligand bonding and play a vital role in many catalytic processes. − Homonuclear iron and copper carbonyls have been extensively studied both experimentally and theoretically. The Fe­(CO) 5 , Fe 2 (CO) 9 , and Fe 3 (CO) 12 compounds are well-known stable iron carbonyls. − The radical anion Fe 3 (CO) 11 – , the dianions Fe 3 (CO) 11 2– and Fe 4 (CO) 13 2– , and the cations Cu­(CO) n + ( n = 1–4) have been prepared in the condensed phase as salts with counterions and characterized spectroscopically. − Unsaturated homoleptic iron and copper carbonyl neutrals as well as ions have been prepared in solid noble gas matrices at cryogenic temperatures and characterized by various spectroscopic methods including infrared absorption (IR), UV–visible, and electron spin resonance (ESR) spectroscopy. − Their geometric and electronic structures are determined, and their bonding is discussed.…”