Thermoemission of singlet oxygen and chemical structure of copper oxides

Thermal treatment of copper oxides (CuO, Cu₂O) is accompanied by large-scale emission of singlet oxygen molecules (¹Σ⁺ _g ). Electron spectroscopy for chemical analysis (ESCA) and electronic and IR spectroscopy were used to show that the thermoemission of electronically excited molecules results from dark generation of electronically excited states which contain in their structure isolated metal-metal bonds and oxygen associates. The anomalous diamagnetic response of the samples and reduced thermoemission activity (Cu₂O) are associated with cooperative interaction of electronically excited states.