DFT calculations of the binding energy of metallocenes

Synthesis of protonated ferrocene isomers in the gas phase and their study by mass spectrometry

“…5 Density functional theory (DFT) calculations at the BPW91/6-311G level of theory predict the metal-protonated and agostic forms to be close in energy. 16 Coupled-cluster calculations 4 give a theoretical proton affinity of ferrocene which is close to the experimental value, predicting the agostic form to be the more stable by 11 kJ mol -1 . This technique failed, however, to yield a minimum energy for the ring-protonated isomer.…”

“…This entropic restriction is, probably, what makes it a relatively slow reaction, even though it is slightly exothermic. Two different conformations are required in the two reaction channels (15) and (16). NH 4 + is of the right size and structure to straddle across the two rings (3b), from which configuration ready transfer into the agostic position could be accomplished easily on either ring (see Figure 7).…”

“…Attempts to calculate the energies and structures of protonated ferrocene by molecular orbital (MO) theory calculations have yielded mixed results. 4,5,[14][15][16] At the MP2/6-311G level of MO theory the ring-protonated form is 176 kJ mol -1 higher in energy than the metal-protonated version. 5 Density functional theory (DFT) calculations at the BPW91/6-311G level of theory predict the metal-protonated and agostic forms to be close in energy.…”

Organometallic molecular modelling - the computational chemistry of metallocenes: a review

“…42 Calculations of the binding energy of various metallocenes (M = Fe, V, Mn, Ni, Ru) reported by Mayor-Lo  pez and Weber 43 do not yield better results than those obtained by Klopper and Lu È thi using ab initio methods. 39 Whilst the geometry of ferrocene was reproduced well at the BPW91 level (LDA augmented by gradient-based corrections to the exchange correlation potential due to Becke and Perdew and Wang respectively), bond length deviations for the other compounds were larger.…”

Efficient Synthesis of Tris(acetonitrile)‐(η5‐cyclopentadienyl)‐ ruthenium(II) Hexafluorophosphate via Ruthenocene

“…Ruthenocene is more robust than ferrocene [15] and no exchange takes place under the conditions of the ferrocene reactions (AlCl 3 , Al, methylcyclohexane, 80 ± 100 8C). [16] Raising the temperature to 165 8C does give the arene complexes, albeit in very low yields (5 ± 15% with the arenes benzene, biphenyl, chlorobenzene and naphthalene).…”