title: Free reaction enthalpy profile of the Schrock cycle derived from density functional theory calculations on the full [Mo(HIPT)N3N] catalyst.
abstract: A series of density functional theory (DFT) calculations on the full [Mo(HIPT)N3N] catalyst are performed to obtain an energy profile of the Schrock cycle. This is a continuation of our earlier investigation of this cycle in which the bulky hexaisopropyterphenyl (HIPT) substituents of the ligand were replaced by hydrogen atoms (Angew. Chem., Int. Ed. 2005, 44, 5639). In an effort to provide a treatment that is as converged as possible from a quantum-chemical point of view, the present study now fully takes the HIPT moieties into account. Moreover, structures and energies are calculated with a near-saturated basis set, leading to models with 280 atoms and 4850 basis functions. Solvent and scalar relativistic effects have been treated using the conductor-like screening model and zeroth-order regular approximation, respectively. Free reaction enthalpies are evaluated using the PBE and B3LYP functionals. A comparison to the available experimental data reveals much better agreement with the experiment than preceding DFT treatments of the Schrock cycle. In particular, free reaction enthalpies of reduction steps and NH3/N2 exchange are now excellently reproduced.
authors.affiliation: Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, D-24118 Kiel, Germany.
authors.forename: Wulf
authors.initials: W
authors.lastname: Thimm
authors.affiliation: Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, D-24118 Kiel, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Gradert
authors.affiliation: Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, D-24118 Kiel, Germany.
authors.forename: Henning
authors.initials: H
authors.lastname: Broda
authors.affiliation: Max-Planck-Institut für chemische Energiekonversion , Stiftstraße 34-36, D-45470 Mülheim an der Ruhr, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Wennmohs
authors.affiliation: Max-Planck-Institut für chemische Energiekonversion , Stiftstraße 34-36, D-45470 Mülheim an der Ruhr, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Neese
authors.affiliation: Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, D-24118 Kiel, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Tuczek
mesh_terms: D002384:Catalysis; D008958:Models, Molecular; D015394:Molecular Structure; D008982:Molybdenum / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D009942:Organometallic Compounds; D008982:Molybdenum