A DFT Comparative Study of Cyclo[18] Nanorings: Carbon, BN and BCN

Activation and Conversion of Molecular Nitrogen to the Precursor of Ammonia on Silicon Substituted Cyclo[18]Carbon: a DFT Design

“…Out of the three combinations, the BN-18 nanoring has been reported to have the highest thermal stability. [32] Recently, mechanistic studies about CO 2 reduction using cyclo [18]carbon catalyst has shown some light on its efficacy [33] to be a potential catalyst. Another group has reported the interactions and mechanistic study of cyclo [18]carbon with triplet oxygen.…”

“…Both the BN‐18 and BCN‐18 have been reported to be stable and could be synthesized. Out of the three combinations, the BN‐18 nanoring has been reported to have the highest thermal stability [32] . Recently, mechanistic studies about CO 2 reduction using cyclo[18]carbon catalyst has shown some light on its efficacy [33] to be a potential catalyst.…”

Cyclo[n]carbons and catenanes from different perspectives: disentangling the molecular thread

“…Electronic properties of boron-and nitrogen-containing analogues of C 18 were studied by Raeber and Mazziotti, using a reduced density matrix approach, 74 and by Barbosa et al at the DFT (oB97X-D/Def2-TZVP). 75 Baryshnikov et 66 showing that the S-T gaps are oscillating in 4k + 2/4k rings for small k and gradually decrease for k 4 15 (implying n 4 60). This behaviour is understandable in connection with the lowering of the HOMO/LUMO gap for increasing n, in other words, the properties of the large cyclo[n]carbons are approaching those of solids.…”

“…Electronic properties of boron- and nitrogen-containing analogues of C 18 were studied by Raeber and Mazziotti, using a reduced density matrix approach, 74 and by Barbosa et al at the DFT (ωB97X-D/Def2-TZVP). 75 Baryshnikov et al in their study of a larger series of cyclo[ n ]carbons (with even n = 6, 100) 76 have found the “turning point” for n > 50, where the difference between the aromaticity/antiaromaticity becomes meaningless and the larger rings become nonaromatic. Similar papers investigating the cyclo[ n ]carbon series with increasing n were published recently.…”

Exploring the Aromaticity Differences of Isoelectronic Species of Cyclo[18]carbon (C18), B6C6N6, and B9N9: The Role of Carbon Atoms as Connecting Bridges

“…Due to the different electronegativities of B, C, and N atoms, these two heteroatomic nanorings are expected to exhibit some distinctive characters that are different from those of C 18 . Motivated by the studies on C 18 , research studies on B 9 N 9 composed of alternating B and N atoms have been repeatedly reported. ,− In contrast, B 6 C 6 N 6 , the spacer substitution product by the B and N atoms of C 18 , has not received much attention from researchers, and its various properties are poorly understood. We noticed that the unimolecular study of B 6 C 6 N 6 was only recently addressed in the work by Barbosa et al The thermodynamic and kinetic stability of B 9 N 9 and B 6 C 6 N 6 nanorings, meanwhile, has been confirmed by theoretical works, making them potential targets for experimental synthesis. , …”