Effects of hydrogen-bond and cooperativity in the vibrational spectra of Luminol

Luminol, one of the most popular electrochemiluminescence systems used in forensic chemistry, proved to be a suitable system to study the importance of cooperativity in hydrogen-bond chains. The computational pairwise approach PiMM was applied to the system and a thorough band assignment was accomplished. Hydrogen-bond and hydrogen-bond cooperativity effects were assessed through a confrontation of energy, geometry and wavenumber changes from monomer and dimer on one hand and dimer and “full-cluster” trimer on the other. For the first time the PiMM method was also used to successfully predict changes in band relative intensities.