The vibronic structures of absorption and magnetic circular dichroism (MCD) in the low energy 11B2u and 11B3u states of 1,4,5,8-naphthalenetetracarboxy dianhydride. The analysis in terms of DFT and CASSCF methods

The magneto-optical properties in low energy 11B2u and 11B3u states of 1,4,5,8-naphthalenetetracarboxy dianhydride (NTCDA) are examined in terms of time-dependent density functional theory at TD-B3LYP/aug-cc-pVDZ and TD-SVWN/aug-cc-pVDZ levels. The Franck–Condon (FC) analysis performed for two 11Ag → 11B2u and 11Ag → 11B3u overlapping transitions led to excellent agreement between the theory and experiment providing that the calculated absorption and MCD spectra are confronted with those measured in chloroform. We argue that absorption and MCD spectra measured in ethanol solution and already known in literature do not characterize NTCDA molecule. Rather, these spectra diagnose a product of chemical reaction between NTCDA and ethanol solvent.