Tracing dynamic self-disassociation behavior of pyrrole with novel T-shaped hydrogen bonding

Near infrared spectroscopy (NIR) and two-dimensional correlation spectroscopy (2Dcos) were employed to study the dynamic self-disassociation behavior of hydrogen bonds in neat liquid pyrrole during heating. Two regions (7000-6430 cm(-1) for NH-related vibrational overtones and 6200-6100 cm(-1) for CH-related vibrational overtones and combination modes) are the focus of this paper, whose integral absorption temperature dependence exhibited a continuous convex variation. Two-dimensional correlation analysis has discerned the sequence of change of different aggregated species of pyrrole. Additionally, we carefully investigated the band shift phenomenon of N-H...pi hydrogen bonding in pyrrole dimers, and assigned this band shift as the result of the transformation of pyrrole dimers from T-shaped geometry to antiparallel geometry.