Novel organic paramagnetic nanofibers and nanostructures: A spectroscopic investigation

► TEMPOL-TDAA aggregates into morphologies that depend on substrate interaction. ► μ-PL spectroscopy reveals crystalline nature of needle-like aggregates and nanofibers. ► Polarized PL emission is detected parallel to aggregates growth direction. ► A preferred head-to-tail interaction drives the molecules in a co-linear arrangement.