ELECTRON-SPIN-RESONANCE OF EXCITED-STATES OF THE H3 AND H4 CENTERS INIRRADIATED TYPE IA DIAMONDS

Electron spin resonance spectra, denoted W26 and W25, observed in type Ia diamonds showing the H3 and H4 optical absorptions, respectively, are shown to be due to excited states of the defects responsible for t hese absorptions. Zero-field and hyperfine parameters have been determ ined and are presented in this paper. The models proposed earlier by L oubser and van Wyk for the H4/W25 defect, and thus by extension also f or the B nitrogen aggregate, are confirmed by the present work. The ES R results also support the the model proposed by Davies for the H3 cen tre.