Aromaticity of rings-in-molecules (RIMs) from electron localization-delocalization matrices (LDMs)

作者：Sumar Ismat^*; Cook Ronald; Ayers Paul W; Matta Cherif F

来源：Physica Scripta, 2016, 91(1): 013001.

DOI：10.1088/0031-8949/91/1/013001

• local aromaticity
• polycyclic aromatic hydrocarbons (PAHs)
• harmonic oscillator model of aromatcity (HOMA)
• aromatic fluctuation index (FLU)
• para delocalization index (PDI)
• nucleus independent chemical shift (NICS)
• multidimensional scaling (MDS)

A new and powerful molecular descriptor termed the LDM (localization-delocalization matrix) has recently been proposed as a molecular fingerprinting tool and has been shown to yield robust quantitative-structure-to-activity/property-relationships (QSAR/QSPR). An LDM lists the average number of electrons localized within an atom in a molecule along its diagonal while the off-diagonal elements are the pair-wise average number of electrons shared between every pair of atoms in the molecule, bonded or not. Hence, the LDM is a representation of a fuzzy molecular graph that accounts for the whereabouts of all electron(s) in the molecule and can be expected to encode for several facets of its chemistry at once. We show that the LDM captures the aromatic character of a ring-in-a-molecule by comparing the aromaticity ranking based on the LDMs and their eigenvalues of 6-membered carbon rings within (polycyclic) benzenoid hydrocarbons with the ranking based on four well-established local aromaticity measures (harmonic oscillator model of aromaticity, acromatic fluctuation index, para delocalization index, and nucleus independent chemical shift(0)).

• 出版日期2016-1