21. Fe(η⁵-Cp)(η¹-Cp)(CO)₂ is a classic organometallic complex with two Cp ligands (Cp = C₅H₅⁻ = cyclopentadienyl) having different coordination modes. Note: η¹-Cp is written as κ¹-Cp in the IUPAC convention. (10%)
(a) Draw the molecular structure of the complex. Remember to include H atoms and indicate double, triple, and aromatic bonds when necessary. (4%)
(b) ¹H NMR spectroscopy of the complex at room temperature only shows two signals, with one from η⁵-Cp and the other from η¹-Cp. Is this result consistent with the molecular structure you draw in (a)? Explain why this is the case and what experiment you would do to verify your explanation. (6%)