Is graphene aromatic?

Abstract

We analyze the chemical bonding in graphene using a fragmental approach, the adaptive natural density partitioning method, electron sharing indices, and nucleus-independent chemical shift indices. We prove that graphene is aromatic, but its aromaticity is different from the aromaticity in benzene, coronene, or circumcoronene. Aromaticity in graphene is local with two π-electrons delocalized over every hexagon ring. We believe that the chemical bonding picture developed for graphene will be helpful for understanding chemical bonding in defects such as point defects, single-, double-, and multiple vacancies, carbon adatoms, foreign adatoms, substitutional impurities, and new materials that are derivatives of graphene.

New Mechanistic Insights on Na-Ion Storage in Nongraphitizable Carbon

“…The plethora of different morphological defects indicates that each type may have its own respective sodiation voltage, thereby giving the sodiation of defects a slope-like shape on the potentiogram curve. Furthermore, considering the delocalized nature of electrons of graphene, 37 binding of a sodium-ion at defect sites is more energetically favorable, as the defect sites have low energy unfilled molecular orbitals that can effectively store extra electrons. This increases the binding energy with sodium and thus allows the sodiation to happen at higher voltages vs Na + / Na.…”

Ribbon Aromaticity of Double-Chain B2n C2H2 Clusters (n = 2–9): A First Principle Study

“…4, the conjugated delocalized p bonds are four-or three-centered over the B 4 rhombus and triangle CB 2 units in B 4 C 2 H 2 , B 8 C 2 H 2 , B 12 C 2 H 2 and B 16 C 2 H 2 . The multi-centered characteristics of the AdNDP p orbitals demonstrate that the double-chain boron ribbons possess local aromaticity (or island aromaticity), just as the local aromaticity in graphene [50].…”

“…In many aromatic approaches, the nucleus-independent chemical shift (NICS) value is a simple and efficient probe [47,48], and adaptive natural density partitioning (AdNDP) approach provides an intuitive description [49,50]. However, an intensive analysis is still absent for the planar boron clusters.…”

Testing the effectiveness of the isoelectronic substitution principle through the transformation of aromatic osmathiophene derivatives into their inorganic analogues

“…This is done in order to recover both Lewis bonding elements (1c-2e or 2c-2e, i.e., lone pairs or two-center two-electron bonds) and delocalized bonding elements, which are associated with the concepts of aromaticity. The AdNDP method has been previously applied to analyze the chemical bonding and aromaticity in both organic [37][38] and inorganic systems. [39][40][41][42] AdNDP analyses were performed with the Multiwfn program.…”