ELECTRONIC AND MOLECULAR-STRUCTURES OF QUINTET BISNITRENES AS STUDIEDBY FINE-STRUCTURE ESR-SPECTRA FROM RANDOM ORIENTATION - ALL THE DOCUMENTED ZFS CONSTANTS CORRECT

A quintet ground-state bisnitrene, 1,3-dinitreno-5-nitrobenzene, was s tudied by randomly oriented ESR spectroscopy as part of our project to study purely organic magnetism and supramolecular functionality expec ted for high spin systems. An observed ESR spectrum of the bisnitrene was interpreted using S=2, g=2.003, \D\=0.224 cm(-1), and \E\=0.038 cm (-1). The determined fine-structure parameter D and E values are in ac cord with our semiempirical treatment for the quintet state in terms o f the fine-structure tensor of the triplet state of p-nitrophenylnitre ne. In this work, we emphasize that all the documented fine-structure parameters D and E for quintet bisnitrenes do not reproduce the corres ponding observed fine-structure ESR spectra from random orientation.