SPECTROSCOPIC STUDY OF SOLID BDNT AND ITS MONOCATION AND DICATION SALTS

The polarized reflection spectra of BDNT, BDNT-PF6 and BDNT-(PF6)(2) have been measured on several crystal faces of the single crystals and compared with the solution spectra of BDNT, BDNT+ and BDNT2+. The spectra of the BDNT crystals have been successfully interpreted in terms of the theory of directional dispersion. Based on this interpretation, the electronic spectra of BDNT, BDNT+ and BDNT2+ have been reasonably assigned to the electronic transitions expected from the molecular orbital calculations. We found a disproportionation reaction in the acetonitrile solution of m-BDNT-PF6, which means that the dication state is close to the monocation state. This is in accord with the low excitation energy (3.5 x 10(3) cm(-1)) of the charge-transfer band in m-BDNT-PF6. The vibrational bands of BDNT, m-BDNT-PF6 and BDNT-(PF6)(2) are presented and discussed.