Analysis of complexity measures and information planes of selected molecules in position and momentum spaces

Abstract

The Fisher–Shannon and LMC shape complexities and the Shannon–disequilibrium, Fisher–Shannon and Fisher–disequilibrium information planes, which consist of two localization–delocalization factors, are computed in both position and momentum spaces for the one-particle densities of 90 selected molecules of various chemical types, at the CISD/6-311++G(3df,2p) level of theory. We found that while the two measures of complexity show general trends only, the localization–delocalization planes clearly exhibit chemically significant patterns. Several molecular properties (energy, ionization potential, total dipole moment, hardness, electrophilicity) are analyzed and used to interpret and understand the chemical nature of the composite information–theoretic measures above mentioned. Our results show that these measures detect not only randomness or localization but also pattern and organization.