title: Theoretical elucidation of a classic reaction: protonation of the quadruple bond of the octachlorodimolybdate(II,II) [Mo2Cl8]4- anion.
abstract: The protonation reaction of the unbridged quadruple metal-metal bond of [Mo(2)Cl(8)](4-) anion producing the triply bonded hydride [Mo(2)(μ-H)(μ-Cl)(2)Cl(6)](3-) is studied by accurate Density Functional Theory computations. The reactant, product, stable intermediates, and transition states are located on the potential energy surface. The water solvent is explicitly included in the calculations. Full reaction profiles are calculated and compared to experimental data. The mechanism of the reaction is fully elucidated. This involves two steps. The first is a proton transfer from an oxonium ion to the quadruple bond, being rate determining. The second, involves the internal rearrangement of chlorine atoms and is much faster. Activation energies with a mean value of 19 kcal/mol are calculated, in excellent agreement with experimental values.
authors: Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece. msim@eie.gr
authors: Emmanuel D
authors: ED
authors: Simandiras
authors: Metaxia
authors: M
authors: Tsakiroglou
authors: Nikolaos
authors: N
authors: Psaroudakis
authors: Dimitrios G
authors: DG
authors: Liakos
authors: Konstantinos
authors: K
authors: Mertis
mesh_terms: D000838:Anions / Q000737:chemistry; D017606:Chlorine Compounds / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D008982:Molybdenum / Q000737:chemistry*; D011522:Protons; D011789:Quantum Theory
chemical_list: D000838:Anions; D017606:Chlorine Compounds; D011522:Protons; C044659:molybdate; D008982:Molybdenum