Enumeration and classification of coronoid hydrocarbons. 10. Double coronoids

A C216-Nanographene Molecule with Defined Cavity as Extended Coronoid

“…Three decades later, in 2012, the third example of cycloarene, namely septulene with 14 benzene rings, was reported by King et al Investigations of the electronic and structural properties of these cycloarenes suggest π-electron localized sextets rather than delocalized aromatic systems, thus supporting Clar’s model over the so-called kekulé structure . The known cycloarenes belong to the subgroup of primitive coronoids, having a hole surrounded by a single band of hexagons, as opposed to the, up until this publication, theoretical coronoids with more bands of hexagons . The geometry of coronoid molecules can be generally understood as polycyclic aromatic hydrocarbons (PAHs) with a cavity of at least two hexagons. , Extended PAHs, such as C42 (with 42 sp 2 carbons; hexa- peri -hexabenzocoronene), C60 , C96 , and C222 , can be regarded as nanographene molecules, which hold promise for potential (opto-)­electronic applications, and also serve as defined model structures of graphene .…”

“…6 The geometry of coronoid molecules can be generally understood as polycyclic aromatic hydrocarbons (PAHs) with a cavity of at least two hexagons. 6,7 Extended PAHs, such as C42 (with 42 sp 2 carbons; hexa-perihexabenzocoronene), 8 C60, 9 C96, 10 and C222, 11 can be regarded as nanographene molecules, which hold promise for potential (opto-)electronic applications, 12 and also serve as defined model structures of graphene. 13 Recently, graphene with regular pores, which is called graphene nanomesh (GNM), has been demonstrated to have an open band gap, in contrast to zero-band gap graphene, highlighting the significant influence of the pore on the electronic features.…”

“…The known cycloarenes belong to the subgroup of primitive coronoids, having a hole surrounded by a single band of hexagons, as opposed to the, up until this publication, theoretical coronoids with more bands of hexagons . The geometry of coronoid molecules can be generally understood as polycyclic aromatic hydrocarbons (PAHs) with a cavity of at least two hexagons. , Extended PAHs, such as C42 (with 42 sp 2 carbons; hexa- peri -hexabenzocoronene), C60 , C96 , and C222 , can be regarded as nanographene molecules, which hold promise for potential (opto-)­electronic applications, and also serve as defined model structures of graphene . Recently, graphene with regular pores, which is called graphene nanomesh (GNM), has been demonstrated to have an open band gap, in contrast to zero-band gap graphene, highlighting the significant influence of the pore on the electronic features .…”

Enumeration of Poly-5-catafusenes Representing a Class of Catacondensed Polycyclic Conjugated Hydrocarbons

“…These drawings were produced systematically by considering the different constellations of pentagons or hexagons, which are possible. It is an approach which resembles the systematic constructions of double coronoids 7 The tri-5-catafusenes with r = 3, 4, 5.…”

Analytical Study of Superaromaticity in Cycloarenes and Related Coronoid Hydrocarbons

“…TRS coronoid hydrocarbons were first depicted by Cyvin et al 70 These coronoids must be the best examples in which highly aromatic rings are isolated from each other and fixed as aromatic sextets. In order to see if the mobility of π-electrons really are limited in such species, SSEs for two typical TRS coronoids (16 and 17 in Figure 9) were calculated and are listed in Table 5.…”