The spectroscopy of the indazole molecule is of considerable interest for the tendency of the molecule to form hydrogen-bonded dimers and larger clusters. In the dimer, the excited electronic states exhibit weak exciton splittings which mimic similar interactions in nucleobase pairs.

Important papers:

• H. Nicken, F. Temps, E. Jalviste, "Dispersed Fluorescence Spectra of 1H- and 1D-Indazole", Z. Phys. Chem. 225, 1457 - 1469 (2011). DOI: 10.1524/zpch.2011.0197.
• E. Jalviste, S. Dziarzhytski, F. Temps, "Electronic Spectra of Hydrogen-Bonded Self and Water Complexes of Indazole", Z. Phys. Chem. 222, 695 - 714 (2008).  DOI: 10.1524/zpch.2008.5347