Electronic states and spin characterization of polyanionic high-spin molecules and clusters derived from 1,3-dibenzoylbenzene derivatives as studied by ESR/electron spin transient nutation spectroscopy

The systems under study were 1,3-dibenzoyl benzene (1), its methyl derivati ves (2,3), and 2,6-dibenzoyl pyridine (4), all of which have topologically pseudogenerate pi-LUMO's. The corresponding dianions are expected to form t riplet ground states and the anionic molecular assemblages expected to form polyanionic high-spin clusters. The polyanionic molecules and clusters wer e generated by chemical reduction and investigated by cw/FT pulsed ESR spec troscopy. Alkali metal-bridged high-spin clusters were identified directly by FT pulsed ESR-based 2D Electron Spin Transient Nutation (2D-ESTN) spectr oscopy. We found ground-state quintet, quarter, and triplet dimers originat ing in the oligoketone with pluri-electron doping. We determined all the ze ro-field splitting parameters, g-values, and the concentration ratio of the high-spin systems with the help of spectral simulation.