Circular dichroism and absorption studies of (‐)‐2,2′‐dimethyl‐4,5‐(1‐naphthyl)‐1,3‐dioxolane in terms of vibronic coupling theory

Abstract

The absorption and circular dichroism (CD) spectra of (-)-2,2'-dimethyl-4,5-(1-naphthyl)-1,3-dioxolane (DND) were studied in the energy region 30,000 cm(-1) to 50,000 cm(-1). The DND ketal is treated as a naphthalene dimer and its spectra are interpreted in terms of a vibronic dimer model which includes the (1)L(a) and (1)B(b) states of the naphthalene chromophore. To fix the most stable conformation of DND molecule, the MNDO/AM1, RHF/6-31G, and SVWN5, BPW91 methods are employed with 6-31G and 6-31G(d',p') basis sets. All the methods are shown to yield the DND geometry that is entirely consistent with the CD and absorption spectra studied.

The resonance and pre‐resonance Raman scattering in the low energy 11B2u and 11B3u states of 1,4,5,8‐naphthalenetetracarboxy dianhydride in terms of DFT methods. The aggregation of NTCDA molecules in the ethanol and methanol solutions

“…The computations yield: ξ = 3.351 and y = 1.485 Å. At this stage, we could treat (NTCDA) 2 as a system of two interacting chromophores in the manner described earlier . So, if one of two is excited to an electronic state Φ(X) (X = 1 1 B 2u , 1 1 B 3u ), but the second one is in the ground state Φ(A g ), the electronic excitation can be localized at two states Φ A (X)Φ B (A g ) and Φ A (A g )Φ B (X) of the dimeric system.…”