Anion Photoelectron Spectroscopy and Quantum Chemical Calculations of LaCu2On‾/0 (n=4-5): Interaction between Oxygen Unit and LaCu2O3 Six-Membered Ring

We conducted a joint anion photoelectron spectroscopy and theoretical investigation on hybrid lanthanum-copper oxides clusters, LaCu2On−/0 (n=4, 5). The experimental vertical detachment energies of LaCu2O4− and LaCu2O5− are determined to be 3.70 and 3.79 eV, respectively. Theoretical calculations show that the most stable structures of LaCu2O4,5− are mainly composed of LaCu2O3 six-membered ring, with an additional O atom or O2 unit interacting with the La atom. In LaCu2O4−, covalent interaction is presented between the external O atom and the LaCu2O3 six-membered ring. As for LaCu2O5− anion, a weak interaction dominated by inductive force is presented between the external O2 unit and the LaCu2O3 six-membered ring.