A series of five bicyclic guanidinate compounds containing various combinations of five- and six-membered rings and substituted alkyl groups have been shown by photoelectron spectroscopy to be easily ionized, with the one having two six-membered rings and four ethyl groups being the most easily ionized. The corresponding anions are capable of forming paddlewheel compounds having quadruply bonded Mo24+ units which are also easy to ionize. The most easily ionized compound is the ethyl-substituted Mo 2(TEhpp)4 complex which has a broad first ionization band centered around 4.27 ± 0.03 eV and an ionization onset at the very low energy of 3.93 ± 0.03 eV. Even the compound with ligands containing two five-membered rings, which favors a long Mo-Mo separation because of the large ligand bite, has an ionization energy (4.78 eV) that is less than those of well-known organometallic reducing agents such as (η5-C 9Me7)2Co and (η5-C 5Me5)2Cr.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry