An ENDOR study of alkali metal–fluorenone biradicals randomly oriented in a rigid matrix

Abstract
An ENDOR study has been made of alkali metal–fluorenone biradicals (M+F−)2 randomly oriented in a rigid matrix. By an appropriate selection of the magnetic field settings in the ESR spectrum, ENDOR signals are obtained that convey information on signs and magnitudes of hyperfine splittings along specific axes in the dimer. The ENDOR spectra also give information on the 23Naquadrupoletensor components in (Na+F−)2. The information gives an insight into the structure of the dimers.