Surface Defect Centres on MgO

In the above sequence of reactions, each step leads to a paramagnetic EPR-visible surface species (indicated in bold). 

The various paramagnetic species, with well known surface chemistry, were better characterised on the basis of extremely well resolved powder spectra and were associated with specific infrared bands of other surface species in interaction with them. For instance in the case of surface 0 lc ions (a species characterised by 011 0e), three species with different 0 values (2.046, 2.036, 2.024) were observed and assigned to specific surface sites in different coordinative environments. More recently, another paper from the same group investigated the surface excitation phenomena using the method of wavelength-selective excitation and related the different paramagnetic O species to the excitation of 

A parallel experimental and theoretical investigation of electron-deficient surface O ions at the surface of MgO, formed by reaction of surface-trapped electrons (Fs ) with N2O, has also been recently reported. The centres form according to the reaction  

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