PorphyStruct - Structural Analysis of Porphyrinoids

While the non-planar displacements of porphyrins and their consequences on both chemical and physical properties were investigated using the NSD method of J. A. Shelnutt and its reimplementation by C. J. Kingsbury and M. O. Senge, such a method did not exist for other porphyrinoids, like corroles, for a long time. PorphyStruct is a digital tool for the quantitative analysis of out-of-plane distortion modes for a variety of porphyrinoids. An analysis of the vibrational normal modes obtained by DFT calculations showed that the established non-planar vibrational modes of porphyrins - Doming, Saddling, Ruffling, Waving (X, Y) and Propellering, are also observable in the less symmetric porphyrinoids. These are used describe and quantify the conformations of corroles and other macrocycles. As in the NSD method, the minimal basis is formed from the first set of the 6 vibrational modes - the extended basis includes another set of the 6 vibrational modes.

An examination of already published corroles showed a peculiarity in copper corroles - they can only be described with the extended basis and show a substantial amount of both saddling variants – we called this phenomenon “Supersaddling”.