Ionization efficiency data and fragmentation mechanisms for ferrocene, nickelocene, and ruthenocene

Abstract

Ionization efficiency (lE) data for the M⁺, MCp⁺, and MCp₂⁺ ions of ferrocene (FeCp₂), nickelocene (NiCp₂), and ruthenocene (RuCp₂) are interpreted by a deconvolution–convolution technique to yield ionic bond dissociation energies in the 6–7 eV range for D(CpM^+–Cp) and in the 4–5 eV range for D(M^+–Cp). Additional direct experimental evidence in support of these values was obtained from lE data for appropriate metastable ion transitions.

Probable errors in the interpretation of lE data for other molecular systems are discussed with reference to the approach for metallocenes presented here.