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Updated: Jul 6, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Electronic structure of the ground and excited states of beta-carboline
Vicente Pérez Mondéjar1, Inmaculada García Cuesta, Paolo Lazzeretti
1Instituto de Ciencia Molecular, Universidad de Valencia, P.O. Box 22085, 46071 Valencia, Spain.
Abstract:
Coupled-cluster calculations are used to compute the energy of conversion between the neutral and the zwitterionic forms of beta-carboline. The stability of the different species is discussed in terms of charge separation and aromatic character, which is related to magnetic criteria. By means of a linear response formalism the vertical excitation energies and oscillator strengths of the lowest singlet states of both structures as well as of the cationic species are determined. General agreement of the relative position and intensity of the different peaks with experimental data is achieved, but the overall spectra are slightly displaced because of solvent effects.
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