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Herein, we explore, from a theoretical perspective, the nonradiative photoinduced processes (charge separation and energy transfer) within a family of donor–acceptor supramolecular complexes based on the electron-donor truxene-tetrathiafulvalene (truxTTF) derivative and a series of curved fullerene fragments (buckybowls) of different shapes and sizes (C30H12, C32H12, and C38H14) as electron acceptors that successfully combine with truxTTF via non-covalent interactions. The resulting supramolecular complexes (truxTTF·C30H12, truxTTF·C32H12, and truxTTF·C38H14) undergo charge-separation processes upon photoexcitation through charge-transfer states involving the donor and acceptor units. Despite the not so different size of the buckybowls, they present noticeable differences in the charge-separation efficiency owing to a complex decay post-photoexcitation mechanism involving several low-lying excited states of different natures (local and charge-transfer excitations), all closely spaced in energy. In this intricate scenario, we have adopted a theoretical approach combining electronic structure calculations at (time-dependent) density functional theory, a multistate multifragment diabatization method, the Marcus–Levitch–Jortner semiclassical rate expression, and a kinetic model to estimate the charge separation rate constants of the supramolecular heterodimers. Our outcomes highlight that the efficiency of the photoinduced charge-separation process increases with the extension of the buckybowl backbone. The supramolecular heterodimer with the largest buckybowl (truxTTF·C38H14) displays multiple and efficient electron-transfer pathways, providing a global photoinduced charge separation in the ultrafast time scale in line with the experimental findings. The study reported indicates that modifications in the shape and size of buckybowl systems can give rise to attractive novel acceptors for potential photovoltaic applications. [ABSTRACT FROM AUTHOR]

In this contribution, we employ computational tools from the energy landscape approach to test Gaussian Approximation Potentials (GAPs) for C60. In particular, we apply basin-hopping global optimization and explore the landscape starting from the low-lying minima using discrete path sampling. We exploit existing databases of minima and transition states harvested from previous work using tight-binding potentials. We explore the energy landscape for the full range of structures and pathways spanning from the buckminsterfullerene global minimum up to buckybowls. In the initial GAP model, the fullerene part of the landscape is reproduced quite well. However, there are extensive families of C1@C59 and C2@C58 structures that lie lower in energy. We succeeded in refining the potential to remove these artifacts by simply including two minima from the C2@C58 families found by global landscape exploration. We suggest that the energy landscape approach could be used systematically to test and improve machine learning interatomic potentials. [ABSTRACT FROM AUTHOR]

In this contribution, we employ computational tools from the energy landscape approach to test Gaussian Approximation Potentials (GAPs) for C60. In particular, we apply basin-hopping global optimization and explore the landscape starting from the low-lying minima using discrete path sampling. We exploit existing databases of minima and transition states harvested from previous work using tight-binding potentials. We explore the energy landscape for the full range of structures and pathways spanning from the buckminsterfullerene global minimum up to buckybowls. In the initial GAP model, the fullerene part of the landscape is reproduced quite well. However, there are extensive families of C1@C59 and C2@C58 structures that lie lower in energy. We succeeded in refining the potential to remove these artifacts by simply including two minima from the C2@C58 families found by global landscape exploration. We suggest that the energy landscape approach could be used systematically to test and improve machine learning interatomic potentials. [ABSTRACT FROM AUTHOR]

The synthesis of new compounds is an important pillar for the advancement of the field of chemistry and adjacent fields. In this regard, over the last decades huge efforts have been made to not only develop new molecular entities but also more efficient sustainable synthetic methodologies due to the increasing concerns over environmental sustainability. In this context, we have developed synthetic routes to novel corannulene flanked imidazolium bromide NHC precursors both in the solid‐state and solution phases. Our work presents a comprehensive comparative study of mechanochemical routes and conventional solution‐based methods. Green metrics and energy consumption comparison were performed for both routes revealing ball‐milling generation of these compounds to be an environmentally greener technique to produce such precursors compared to conventional solvent‐based methods. In addition, we have demonstrated proof‐of‐concept of the herein reported corannulene flanked NHCs to be robust ligands for transition metals and their ligand substitution reactions. [ABSTRACT FROM AUTHOR]

We theoretically investigated the host–guest chemistry between belt-like cycloparaphenylenes (CPPs) and entrapped bowl-shaped sumanene and corannulene. Density functional theory calculations show that the buckybowls can be stabilized in a CPP host with an appropriately sized cavity (e.g., [10]CPP) through multi-site CH–π interactions. Arising from the confined intermolecular interactions within the cavity, the restrictive buckybowls display novel reactivity distinct from that in their free state. [ABSTRACT FROM AUTHOR]

The electronic, optoelectronic, linear and nonlinear optical (NLO) properties of some corannulenes of formula C5n2H5n (with n = [2,4]), doped with boron–nitride units at the rim position, have been studied using density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. This work aims to substitute B–N units at the rim position in some corannulene structures in order to propose new materials for electronic, optoelectronic and nonlinear optical applications. According to the investigations carried out, the analysis of the cohesive energies of the studied corannulene derivatives indicates that they are energetically stable materials. Based on the |HOMO–LUMO| energy gap values, we find that corannulenes doped with B–N units at the rim position exhibit the same semiconducting nature as the parent structure from which they derive. Moreover, the value of first-order hyperpolarizability (β0) of structures containing B–N isoelectronic units at the rim position in corannulenes is higher than that of the urea molecule considered as a reference molecule commonly used in nonlinear optics (NLO). We hope that the present work will also pave the way for the design of high-performance nonlinear optical materials based on boron–nitride-doped corannulene at the rim position. TD/B3LYP-D3/6–31 + G(d) calculations revealed that among the proposed derivatives, the compounds C35B5N5H15 and C70B5N5H20 exhibit high photo-current response in the visible range. This gives these new materials good performances for optoelectronic applications. Although all the studied properties of the doped structures with B–N units at the rim position are not better than those at the spoke position reported in the literature, these proposed systems have good capabilities to be used as suitable organic semiconductors in the photovoltaic field. [ABSTRACT FROM AUTHOR]

The search for new high-performance push-pull materials for use in nonlinear optics (NLO) and optics is currently a popular area of research. In this study, the effects of metal oxides -(MO)n = 1,2 (monomer: MO=TiO2, CuO, Al2O3, and ZnO; and dimer: MO = Ti2O4, Cu2O2, Al4O6, and Zn2O2) on the electronic, absorption, optoelectronic and NLO characteristics of circumcorannulene (CO) in the gas phase and in acetonitrile have been investigated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at the B3LYP and CAM-B3LYP/6-311+G(d,p)/LANL2DZ levels of theory. Research has shown that adding metal oxides to CO leads to the formation of new push-pull CO derivatives. These derivatives include T1, U1, A1, Z1, T2, U2, A2, and Z2 formed from TiO2, CuO, Al2O3, ZnO, Ti2O4, Cu2O2, Al4O6, and Zn2O2 metal oxides, respectively. They exhibit excellent stability, low |HOMO-LUMO| gap energy, high NLO, and photocurrent responses compared to CO in gaseous media and polar solvents. However, it is interesting to note that the use of the copper oxide monomer configuration on corannulene family compounds is effective in improving their NLO response, while increasing the alumina chain proves necessary to improve their photocurrent response in the visible region. [ABSTRACT FROM AUTHOR]

Perovskite solar cell (PSC) shows a great potential to become the next‐generation photovoltaic technology, which has stimulated researchers to engineer materials and to innovate device architectures for promoting device performance and stability. As the power conversion efficiency (PCE) keeps advancing, the importance of exploring multifunctional materials for the PSCs has been increasingly recognized. Considerable attention has been directed to the design and synthesis of novel organic π‐conjugated molecules, particularly the emerging curved ones, which can perform various unmatched functions for PSCs. In this review, the characteristics of three representative such curved π‐conjugated molecules (fullerene, corannulene and helicene) and the recent progress concerning the application of these molecules in state‐of‐the‐art PSCs are summarized and discussed holistically. With this discussion, we hope to provide a fresh perspective on the structure‐property relation of these unique materials toward high‐performance and high‐stability PSCs. [ABSTRACT FROM AUTHOR]

Corannulene (C20H10) is a distinctive type of non-planar conjugated polycyclic aromatic buckybowl which possesses unique chemical and physical properties. In this study, superalkali doped corannulene complexes are theoretically designed and their structural, electronic, and optical properties are investigated using quantum chemical calculations. The superalkalis AM3O (AM = Li, Na, K) are doped over both convex and concave surfaces of corannulene. The interaction energies (− 26.39 to − 53.99 kcal/mol) reflect that the designed AM3O@ C20H10 complexes are thermodynamically stable. Doping of superalkalis has remarkably reduced the HOMO–LUMO energy gaps (0.67–1.47 eV) of the corannulene with enhanced semiconducting properties. The investigation of charge transfer has been performed using natural bond orbital analysis, and one of the K3O doped complex exhibits the largest charge transfer (0.95 |e|). The visualization of charge transfer from the super alkali and the corannulene has been carried out via deformation density analysis. The non-covalent interaction index and quantum theory of atoms in molecules analyses are also conducted to ascertain the nature of interactions in the designed complexes. The static polarizability (326 au) and static first hyperpolarizability (1.6 × 103 au) values of corannulene are considerably enhanced as a result of superalkali doping. Moreover, superalkali doping over convex face exhibited more remarkable enhancement of static hyperpolarizabilities (βo) as compared to concave face doped complexes. These findings might enable the development of effective NLO materials with improved optoelectronic properties. [ABSTRACT FROM AUTHOR]

Corannulenes have received much interest due to their electronic properties, which differ between the convex and concave surfaces of the molecule. The ability to control the shapes of corannulenes to optimize charge distribution is therefore important for the development of seminconductors and electronic devices. In this paper, the interactions of corannulenes are modeled inside carbon nanotubes of various sizes using the Lennard–Jones potential and a continuum approach. The major contribution of this work is the analytical expressions for the interaction energy, which are obtained as a function of the nanotube's radius, the offset distance of corannulene from the tube's axis and the orientation of corannulene. Minimizing this energy, the range of nanotube's radii that allow the corannulene to adopt lying, tilting and standing configurations both on‐ and off‐axis of the nanotubes is determined. These results are supported by the density functional theory calculations and agree with previously published work using molecular dynamics simulations for corannulenes located on the nanotube's axis. [ABSTRACT FROM AUTHOR]

Graphene has been used as a catalyst to reduce the energy barrier for corannulene inversion. For such a catalytic study, corannulene structures are normally assumed to already be in close proximity to graphene, either in the concave-up or concave-down orientation. Here we use both the Lennard-Jones potential (pair-wise dispersion model) and density functional theory calculations to show that corannulene at a distance further away from graphene can adopt various orientations to optimise its interaction with graphene.

Geometric and electronic structures of a corannulene ( C 20 H 10) intercalated bilayer graphene are investigated in terms of the molecular conformation using density functional theory. Our calculations indicate that the electronic structure of bilayer graphene is tunable by controlling the molecular conformation of corannulene. Holes and electrons coexist on the upper and lower layers of graphene, which are situated at the convex region and edge of corannulene when it has the bowl conformation. In contrast, bilayer graphene has a tiny gap of 4.7 meV at the K point owing to the substantial interaction between graphene and corannulene when corannulene has flat conformation. Electron and hole redistribution in bilayer graphene intercalating corannulene indicated the possibility of all carbon p-n border at an interface between corannulene with convex and concave arrangements. The intercalation substantially decreases the energy difference between the ground state bowl conformation and the metastable state flat conformation by approximately 400 meV. Accordingly, the two-dimensional nano-spacing between the graphene layers changes the molecular conformation of corannulene from a bowl to a flat structure at 139 MPa. [ABSTRACT FROM AUTHOR]

Mixed‐valence (MV) dimers have been extensively investigated, however, the structure and properties of purely organic MV trimers based on open‐shell polycyclic aromatic hydrocarbons remain elusive. Herein, unprecedented MV BN‐doped corannulene radical cations [BN‐Cor1]3⋅⋅2+ ⋅ 2[BArylF4]− and [BN‐Cor2]3⋅⋅2+ ⋅ 2[BArylF4]− were synthesized via chemical oxidation, and their structures were unambiguously confirmed by single‐crystal X‐ray diffraction. These uncommon radical cations consist of three corannulene cores and two [BArylF4]− anions, and three corannulene motifs [BN‐Cor1]3⋅⋅2+ and [BN‐Cor2]3⋅⋅2+ in the unit cell exhibit a trimer structure with a slipped π‐stacking configuration. Detailed structural analyses further revealed that the corannulene cores exhibit an infinite layered self‐assembly configuration, allowing their potential applications as building blocks for molecular conductors. The detection of a forbidden transition (Δms=±2) by electron paramagnetic resonance (EPR) spectroscopy further confirmed the existence of two unpaired electrons in the π‐trimers and the MV characteristic of these two species. Variable‐temperature EPR and conductivity measurements suggested that the BN‐doped π‐trimers exhibited antiferromagnetic coupling and conductivity properties. [ABSTRACT FROM AUTHOR]

The current investigation, interaction of Cr(CO)3 fragment with corannulene was examined at the B3LYP*/6-311G(d,p) level of theory. C-PCM study of the formed Cr(CO)3(η6- corannulene) complex was reported. Independent and dependent-frequency isotropic polariazability and first hyperpolarizability values of this complex were calculated. The solvent effect on these data were examined using conductor polarizable continuum model (C-PCM). Correlations of the energetics, electronic and optical properties with modified-Buckingham function (Fmodified-Buckingham) were illustrated. Reduced density gradient (RDG) was employed to analyze the interaction between Cr(CO)3 fragment with corannulene. [ABSTRACT FROM AUTHOR]

Corannulene‐derived materials have been extensively explored in energy storage and solar cells, however, are rarely documented as emitters in light‐emitting sensors and organic light‐emitting diodes (OLEDs), due to low exciton utilization. Here, we report a family of multi‐donor and acceptor (multi‐D‐A) motifs, TCzPhCor, TDMACPhCor, and TPXZPhCor, using corannulene as the acceptor and carbazole (Cz), 9,10‐dihydro‐9,10‐dimethylacridine (DMAC), and phenoxazine (PXZ) as the donor, respectively. By decorating corannulene with different donors, multiple phosphorescence is realized. Theoretical and photophysical investigations reveal that TCzPhCor shows room‐temperature phosphorescence (RTP) from the lowest‐lying T1; however, for TDMACPhCor, dual RTP originating from a higher‐lying T1 (T1H) and a lower‐lying T1 (T1L) can be observed, while for TPXZPhCor, T1H‐dominated RTP occurs resulting from a stabilized high‐energy T1 geometry. Benefiting from the high‐temperature sensitivity of TPXZPhCor, high color‐resolution temperature sensing is achieved. Besides, due to degenerate S1 and T1H states of TPXZPhCor, the first corannulene‐based solution‐processed afterglow OLEDs is investigated. The afterglow OLED with TPXZPhCor shows a maximum external quantum efficiency (EQEmax) and a luminance (Lmax) of 3.3 % and 5167 cd m−2, respectively, which is one of the most efficient afterglow RTP OLEDs reported to date. [ABSTRACT FROM AUTHOR]

Corannulene, a curved polycyclic aromatic hydrocarbon, is prepared in a multigram scale through mechanochemical synthesis. Initially, a mixer mill approach is examined and found to be suitable for a gram scale synthesis. For larger scales, planetary mills are used. For instance, 15 g of corannulene could be obtained in a single milling cycle with an isolated yield of 90 %. The yields are lower when the jar rotation rate is lower or higher than 400 revolutions per minute (rpm). Cumulatively, 98 g of corannulene is produced through the ball milling‐based grinding techniques. These results indicate the future potential of mechanochemistry in the rational chemical synthesis of highly curved nanocarbons such as fullerenes and carbon nanotubes. [ABSTRACT FROM AUTHOR]

The curved π‐conjugated surface of bowl‐shaped corannulene has been multiply methylated to form exo‐di‐, ‐tetra‐, and ‐hexamethylated corannulenes. The multimethylations became possible through in‐situ iterative reduction/methylation sequences that involve the reduction of corannulenes using sodium to form the anionic corannulene species, and the subsequent SN2 reaction of the anionic species with reduction‐resistant dimethyl sulfate. X‐ray diffraction analyses, NMR, MS, UV‐Vis measurements, and DFT calculations have revealed the molecular structures of the multimethylated corannulenes and the sequence of the multimethylation. This work has the potential to contribute to the controlled synthesis and characterizations of multifunctionalized fullerenes. [ABSTRACT FROM AUTHOR]

Fragments of buckminsterfullerene (C60) include the monumental three compounds corannulene, sumanene, and truxene. These three have served as leading molecules in ongoing research for curved, fused, and π‐extended polyaromatic materials. Achieving more structural variations that join the ranks of these three archetypes remains challenging. Herein we report synthesis of an octacyclic hydrocarbon that is an unexplored C60‐fragment, namely, a 4,11‐dihydrodiindeno[7,1,2‐ghi:7′,1′,2′‐pqr]chrysene (C28H16, which we named Metelykene). The key to success was solution‐compatible synthesis in which double pentagonal rings flank hexagonal ones. This solution‐phase approach, coupled with the resulting non‐planar π‐conjugation, is so straightforward that it offers an entry to a derivative such as a cardo aromatic monomer. [ABSTRACT FROM AUTHOR]

Pristine fullerene C60 is an excellent electron transport material for state‐of‐the‐art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high‐quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl‐shaped additive, corannulene, to assist in C60‐assembly into a smooth and compact film through the favorable bowl‐ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60, it also plays a critical role in forming C60‐corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution‐processed‐C60 (SP‐C60) ETL. Moreover, the stability of the CC device is far superior to that of the C60‐only device because corannulene can retard and curb the spontaneous aggregation of C60. This work establishes the bowl‐assisted ball assembly strategy for developing low‐cost and efficient SP‐C60 ETLs with high promise for fully‐SP PSCs. [ABSTRACT FROM AUTHOR]

In this study, we found that a pristine buckybowl, sumanene, can form solution-state supramolecular polymers. We also demonstrated that sumanene supramolecular polymers can be dynamically controlled by external stimuli, in which solvation plays a significant role. This study not only provides new guidelines for the rational design of supramolecular polymers, particularly for the use of buckybowls, but also presents interesting dynamic behaviors of supramolecular polymerization. [ABSTRACT FROM AUTHOR]

A new 15‐membered‐macrocyclic molecular entity, oxa‐TriQuinoline (o‐TQ), was designed and synthesized. In o‐TQ, three oxygen atoms were joined onto three quinoline units at the 2‐ and 8‐positions in a head‐to‐tail fashion by three‐fold SNAr reactions, giving rise to the characteristic N3O3 aza‐oxa‐crown architecture. o‐TQ can serve as a new tridentate nitrogen ligand to capture a CuI cation and adopt a bowl shape, before supramolecular complexation with corannulene and [12]cycloparaphenylene (CPP) occurs through π–π and CH–π interactions. In the presence of the CuI cation, the non‐emissive o‐TQ becomes a highly emissive material in the solid state, whereby the emission wavelengths depend on the ancillary ligand on the CuI cation. The o‐TQ/CuI complex is able to promote carbene catalysis to provide a range of enamines with a gem‐difluorinated terminus. [ABSTRACT FROM AUTHOR]

In an astrochemical and environmental context, this work constitutes a step forward in understanding the photo-reactivity of polycyclic aromatic hydrocarbons (PAHs) with water molecules and in water ice under irradiation with low energy photons. The role of charge transfer states PAH + -H 2 O - has been proposed, motivating the study of the electronic excited states up to about 6 eV of planar and bowl-shaped PAHs, namely pyrene C 16 H 10 and corannulene C 20 H 10 , interacting with water clusters of different sizes and orientations, using a time-dependent density functional theory approach. In the case of pyrene, the systematic occurrence of low energy excitations from π orbitals to diffuse orbitals located on some water molecules, mixed with the Rydberg orbitals (R/wat), was found. Such excitations are more numerous and possess larger oscillator strengths when (i) the number of water molecules increases up to representing a first layer of hexagonal water ice and (ii) for the arrangements leading to the lower vertical ionization potential values. In this case, the /wat orbitals are located on the most external H atoms and they may also mix with π ⋆ orbitals. This accounts for the efficient reactivity of pyrene with water in water ice. In the case of corannulene, the main result is that, for the C 20 H 10 (H 2 O) 3 isomer formed in a noble gas matrix, where (H 2 O) 3 interacts with the concave face of corannulene, no π → R/wat transition is observed. It is in line with the lack of reactivity of corannulene with water in a noble gas matrix. [ABSTRACT FROM AUTHOR]

A scalable, stochastic algorithm evaluating the fourth-order many-body perturbation (MP4) correction to energy is proposed. Three hundred Goldstone diagrams representing the MP4 correction are computer generated and then converted into algebraic formulas expressed in terms of Green's functions in real space and imaginary time. They are evaluated by the direct (i.e., non-Markov, non-Metropolis) Monte Carlo (MC) integration accelerated by the redundant-walker and control-variate algorithms. The resulting MC-MP4 method is efficiently parallelized and is shown to display O(n5.3) size-dependence of cost, which is nearly two ranks lower than the O(n7) dependence of the deterministic MP4 algorithm. It evaluates the MP4/aug-cc-pVDZ energy for benzene, naphthalene, phenanthrene, and corannulene with the statistical uncertainty of 10 mEh (1.1% of the total basis-set correlation energy), 38 mEh (2.6%), 110 mEh (5.5%), and 280 mEh (9.0%), respectively, after about 109 MC steps. [ABSTRACT FROM AUTHOR]

We have studied the production of doubly charged molecular ions by a single photon for the aromatic molecules triphenylene (C18H12) and corannulene (C20H10) using monochromatized synchrotron radiation from 18 eV to 270 eV. We compare our results with previously published data for partially deuterated benzene (C6H3D3), pyrene (C16H10), and coronene (C24H12). The question that we address in this paper is how the different but similar molecular structures of coronene, corannulene, and triphenylene affect the photon-energy dependence of the ratio of doubly to singly charged parent ions. A theoretical analysis of the main features in terms of independent molecular subsystems will be discussed. [ABSTRACT FROM AUTHOR]

Corannulene is a nonplanar aromatic hydrocarbon also known as a buckybowl. Its electronic and vibrational structure has been investigated by analyzing its fluorescence excitation spectrum and dispersed fluorescence spectrum in a supersonic jet. Its spectral features are in keeping with the expectation, confirmed by some previous results, that it has fivefold or C 5 v symmetry. The observed prominent vibronic bands in the S1 ← S0 transition have been assigned to e1 and e2 bands on the basis of theoretical calculations so that the S1 state was assigned to 1E2. The symmetry adapted cluster configuration interaction calculation supports this assignment of the S1 electronic state, although the time-dependent density functional theory calculation suggests that the S1 state is 1A2. It has also been shown that the normal coordinates for strong vibronic bands mainly include out-of-plane vibrational motion. The rotational envelopes are well explained by taking account of the Coriolis interaction between the degenerate vibrational and rotational levels. The mechanism of bowl-to-bowl inversion is also discussed with the results of theoretical calculations regarding the barrier to inversion and metastable conformation. [ABSTRACT FROM AUTHOR]

Synthesis of buckybowls have stayed highly challenging due to the large structural strain caused by curved π surface. In this paper, we report the synthesis and properties of two trichalcogenasupersumanenes which three chalcogen (sulfur or selenium) atoms and three methylene groups bridge at the bay regions of hexa-peri-hexabenzocoronene. These trichalcogenasupersumanenes are synthesized quickly in three steps using an Aldol cyclotrimerization, a Scholl oxidative cyclization, and a Stille type reaction. X-ray crystallography analysis reveals that they encompass bowl diameters of 11.06 Å and 11.35 Å and bowl depths of 2.29 Å and 2.16 Å for the trithiasupersumanene and triselenosupersumanene, respectively. Furthermore, trithiasupersumanene derivative with methyl chains can form host-guest complexes with C60 or C70, which are driven by concave-convex π ⋯ π interactions and multiple C–H ⋯ π interactions between bowl and fullerenes. Synthesis of buckybowls has remained challenging due to the inherent high strain induced by the curvature. Herein, the authors report the synthesis of two bowl-shaped polycyclic aromatics with three chalcogen atoms and three methylene groups embedded at the bay regions of hexa-peri-hexabenzocoronene and demonstrate guest host complexation with trithiasupersumanene. [ABSTRACT FROM AUTHOR]

The dynamic and static nature of the XH-∗-π and YX-∗-π (X = F, Cl, Br, and I; Y = X and F) interactions in the distorted π-system of corannulene (π(C20H10)) is elucidated with a QTAIM dual functional analysis (QTAIM-DFA), where asterisks emphasize the presence of bond critical points (BCPs) on the interactions. The static and dynamic nature originates from the data of the fully optimized and perturbed structures, respectively, in QTAIM-DFA. On the convex side, H in F–H-∗-π(C20H10) and each X in Y–X-∗-π(C20H10) join to C of the central five-membered ring in π(C20H10) through a bond path (BP), while each H in X–H-∗-π(C20H10) does so to the midpoint of C=C in the central five-membered ring for X = Cl, Br, or I. On the concave side, each X in F–X-∗-π(C20H10) also joins to C of the central five-membered ring with a BP for X = H, Cl, Br, and I; however, the interactions in other adducts are more complex than those on the convex side. Both H and X in X–H-∗-π(C20H10) (X = Cl and Br) and both Fs in F–F-∗-π(C20H10) connect to the three C atoms in each central five-membered ring (with three BPs). Two, three, and five BPs were detected for the Cl–Cl, I–H, Br–Br, and I–I adducts, where some BPs do not stay on the central five-membered ring in π(C20H10). The interactions are predicted to have a vdW to CT-MC nature. The interactions on the concave side seem weaker than those on the convex side for X–H-∗-π(C20H10), whereas the inverse trend is observed for Y–X-∗-π(C20H10) as a whole. The nature of the interactions in the π(C20H10) adducts of the convex and concave sides is examined in more detail, employing the adducts with X–H and F–X placed on their molecular axis together with the π(C24H12) and π(C6H6) adducts. [ABSTRACT FROM AUTHOR]

Corannulene (Cor), a special carbon material, evidenced strong protein binding capacity which regulating lysozyme crystallization and controlling reactive oxygen species (ROS) generation. Ion channel protein play role in regulating ion channel functions to affect physiological functions. However, the interaction between Cor and ion channel protein have not been studied. In this study, PEG/Cor nanoparticles (PEG/Cor Nps) were prepared by mPEG-DSPE. The PEG/Cor Nps localized in cytoplasm and produced cytotoxicity at high concentration. Whole cell patch clamp examined ion channel functions after incubate PEG/Cor Nps with PC-12 cell. we found that PEG/Cor Nps inhibited voltage-gated Na+ ion channels in a dose- and time-dependent manner but not act on voltage-gated K+ ion channels. The potential mechanisms were revealed by all-atom molecular dynamic (MD) simulations. The results showed that PEG/Cor Nps block the pore of sodium ion channel protein due to dose- and time-dependent accumulation. Besides, the orientation angle (θ) configuration of PEG/Cor Nps will be inverted with the accumulation to generate two blocking mechanisms. Different from other carbon nanomaterials, the blockage mechanism of PEG/Cor Nps provides novel insights into the mechanisms of interaction between carbon nanomaterials and protein. • PEG/Cor NPS is located in the cytoplasm and is cytotoxic to PC-12 cells at high concentrations. • PEG/Cor NPS suppresses voltage-gated Na + ion channels in a dose- and time-dependent manner. • The orientation angle (θ) configuration of PEG/Cor NPS is reversed with accumulation to generate two blocking mechanisms. • All-atom molecular dynamics (MD) simulations revealed underlying mechanisms. [ABSTRACT FROM AUTHOR]

The present work introduces the mechanochemistry of corannulene under in-plane stress. External force explicitly included (EFEI) DFT calculations reveal that the properties of corannulene, including the curvature and flattening process, the electronic structures, the dynamic concave–convex flipping, and the curved-π host–guest interactions, are monitored by the applied external force and the bowl effects of buckybowls can be controlled as desired, which cannot be achieved by traditional chemical approaches. [ABSTRACT FROM AUTHOR]

In this investigation, a systematic study on the design and development of corannulene‐based thermally activated delayed fluorescence (TADF) emitters using density functional theory methods is carried out. Benzene, benzopyrazine, difluoro‐benzopyrazine, benzene‐1,2‐dithiol, and tetrasulfone are introduced on corannulene bowl as electron‐withdrawing groups to alter the electron‐accepting property of corannulene. Three different donors, viz., carbazole, phenoxazine, and 5,10‐dihydrophenazine are substituted on the rim position of corannulene to alter the absorption properties. The relationship between chemical structure and TADF property is established by evaluating the dihedral angle between donor and acceptor units, spin–orbit coupling (SOC) values, the energy difference between singlet‐triplet excited states (ΔEST), and rates of reverse intersystem crossing (kRISC). The newly designed TADF emitters show absorption in the blue to near‐IR regions depending on the strength of the donor and acceptor moieties. Careful analysis of these properties delineates the relationship between SOC values and the nature of the excited states, which is crucial for achieving high kRISC. [ABSTRACT FROM AUTHOR]

Herein we show that hybridisation of buckybowl corannulene and thiophene‐S,S‐dioxide motifs is a general approach for the preparation of high electron affinity molecular materials. The devised synthesis is modular and relies on thienannulation of corannnulene‐based phenylacetylene scaffolds. The final compounds are highly soluble in common organic solvents. These compounds also exhibit interesting optical properties such as absorption and emission in the blue/green regions of the electromagnetic spectrum. Importantly, a bis‐S,S‐dioxide derivative exhibits three reversible reductions similar in their strength to the prevalent fullerene‐based electron acceptor phenyl‐C61‐butyric acid methyl ester (PC61BM). [ABSTRACT FROM AUTHOR]

The interaction of a curved polycyclic aromatic hydrocarbon (PAH), corannulene (C20H10), with H-atoms leading to the formation of highly superhydrogenated species was studied. In particular, we determined the H-atom addition sequence to a monolayer of corannulene deposited on a graphite surface in order to understand the effect of curvature on the interaction of PAHs with H-atoms. We also investigated why superhydrogenated corannulene species with a certain number of additional H-atoms are more stable than the others. A combination of thermal desorption mass spectrometry measurements and density functional theory calculations was used to reveal and understand the presence of the most stable configurations in the superhydrogenation sequence of corannulene. Specifically, the experiments demonstrate the presence of stable configurations of superhydrogenated corannulene at specific hydrogenation levels of 2, 6, 8, 10, 12, 14, 16, 17, and 18 extra H-atoms. Density functional theory calculations of binding energies and barrier heights explain why some of these configurations are particularly stable and provide new insights into the superhydrogenation of curved PAH molecules under interstellar conditions. [ABSTRACT FROM AUTHOR]

Hydrogenated polycyclic aromatic hydrocarbons have been proposed to be carriers of the interstellar unidentified infrared (UIR) emission bands and the catalysts for formation of H2; spectral characterizations of these species are hence important. We report the infrared (IR) spectrum of mono-hydrogenated corannulene (HC20H10) in solid para-hydrogen (p-H2). In experiments of electron bombardment of a mixture of corannulene and p-H2 during deposition of a matrix at 3.2 K, two groups of spectral lines increased with time during maintenance of the matrix in darkness after deposition. Lines in one group were assigned to the most stable isomer of hydrogenated corannulene, rim-HC20H10, according to the expected chemistry and a comparison with scaled harmonic vibrational wavenumbers and IR intensities predicted with the B3PW91/6-311++G(2d,2p) method. The lines in the other group do not agree with predicted spectra of other HC20H10 isomers and remain unassigned. Alternative hydrogenation was achieved with H atoms produced photochemically in the infrared-induced reaction Cl + H2 (v = 1) → H + HCl in a Cl2/C20H10/p-H2 matrix. With this method, only lines attributable to rim-HC20H10 were observed, indicating that hydrogenation via a quantum-mechanical tunneling mechanism produces preferably the least-energy rim-HC20H10 regardless of similar barrier heights and widths for the formation of rim-HC20H10 and hub-HC20H10. The mechanisms of formation in both experiments are discussed. The bands near 3.3 and 3.4 µm of rim-HC20H10 agree with the UIR emission bands in position and relative intensity, but other bands do not match satisfactorily with the UIR bands. [ABSTRACT FROM AUTHOR]

Perfluorinated cycloparaphenylenes (F‐[n]CPP, n = 5–8), boron nitride nanohoop (F‐[5]BNNH), and buckybowls (F‐BBs) were proposed as anion receptors via anion‐π interactions with halide anions (Cl−, Br− and I−), and remarkable binding strengths up to −294.8 kJ/mol were computationally verified. The energy decomposition approach based on the block‐localized wavefunction method, which combines the computational efficiency of molecular orbital theory and the chemical intuition of ab initio valence bond theory, was applied to the above anion‐π complexes, in order to elucidate the nature and selectivity of these interactions. The overall attraction is mainly governed by the frozen energy component, in which the electrostatic interaction is included. Remarkable binding strengths with F‐[n]CPPs can be attributed to the accumulated anion‐π interactions between the anion and each conjugated ring on the hoop, while for F‐BBs, additional stability results from the curved frameworks, which distribute electron densities unequally on π‐faces. Interestingly, the strongest host was proved to be the F‐[5]BNNH, which exhibits the most significant anisotropy of the electrostatic potential surface due to the difference in the electronegativities of nitrogen and boron. The selectivity of each host for anions was explored and the importance of the often‐overlooked Pauli exchange repulsion was illustrated. Chloride anion turns out to be the most favorable anion for all receptors, due to the smallest ionic radius and the weakest destabilizing Pauli exchange repulsion. [ABSTRACT FROM AUTHOR]

We report the synthesis and late‐stage diversification of a new class of hetero‐buckybowl, BN‐embedded dibenzocorannulenes (B2N2‐DBCs). The synthesis is achieved via one‐shot halogenative borylation, comprising the nitrogen‐directed haloboration of alkyne and an intramolecular bora‐Friedel‐Crafts reaction, which provides BN‐embedded dibenzocorannulene possessing two bromo substituents (B2N2‐DBC‐Br). B2N2‐DBC‐Br undergoes diversification via coupling reactions to provide a variety of arylated derivatives (B2N2‐DBC‐R), exhibiting strong blue fluorescence. An organic light‐emitting diode (OLED) employing one of the derivatives as an emitter exhibited a high external quantum efficiency of 6.6 % and long operational lifetime of 907 h at an initial luminance of 1000 cd m−2, indicating the significant potential for the development of efficient and stable hetero‐buckybowl‐based OLED materials. [ABSTRACT FROM AUTHOR]

Sunlight‐driven photochemical reactions are an important tool for sustainable organic synthesis. However, compared with ground states, for which the effects of structure on properties and reactivity are well established, the understanding of excited states is limited. In particular, an improved understanding of aromaticity and antiaromaticity in excited states is necessary to develop strategic photochemical methods for synthesizing polycyclic aromatic compounds. Herein, using density functional theory (DFT)‐optimized structures, the ground singlet (S0) and lowest triplet (T1) states of coronene and corannulene were compared. Bond length analysis demonstrated that both triplet corannulene and triplet coronene bear a partial resemblance to benzene. Nucleus‐independent chemical shift (NICS(0), NICS(1.7)ZZ, NICS scans) and anisotropy of the induced current density (ACID) calculations were carried out to compare the induced magnetic currents in these molecules. This analysis demonstrated rather weak π‐conjugation and partial antiaromaticity in the S0 state of each molecule. In contrast, a combination of circular induced currents and pronounced antiaromaticity was found in the T1 state of each molecule. However, the T1 of corannulene exhibited higher stability, which should facilitate functionalization. Consequently, corannulene is considered more suitable for photochemical applications. [ABSTRACT FROM AUTHOR]

Aromaticity rules in the ground singlet state and the first excited triplet state are exactly opposite, as shown by Baird. Thus, (4n + 2)π electron annulenes are antiaromatic and 4nπ annulenes are aromatic in their triplet state. In this work, we employ quantum‐mechanical calculations at the density functional theory (DFT) level to examine (anti)aromaticity of singlet and triplet corannulene dianion and dication in their bowl‐shaped ground‐state structure and planar transition‐state structure. We find that singlet dianion contains aromatic hub and antiaromatic rim, whereas singlet dication is an antiaromatic system. This agrees with previous calculations of current density induced by perpendicular magnetic field. For triplet dianion, we find that it can be described as having aromatic rim and nonaromatic hub. Triplet dication was found to be nonaromatic, though in planar transition‐state structure, locally and semiglobally antiaromatic naphthalene subunit and aromatic central ring can be discerned. [ABSTRACT FROM AUTHOR]

2,3,5,6,8,9‐Hexakis(bromomethyl)sumanene, a hexa‐substituted sumanene with bromomethyl groups at the peripheral aromatic carbons, was successfully synthesized in 97% yield with a one‐step reaction. Single‐crystal X‐ray structural analysis showed a formation of a dimer structure. The nucleophilic substitution afforded the introduction of several substituents. These UV‐vis absorption and emission spectra showed clear redshift compared with pristine sumanene, indicating the extension of the conjugation system of hexa‐substituted sumanenes. [ABSTRACT FROM AUTHOR]

The Tl+ corannulene complexes have been proven by ESI-MS method. The structure of these complexes have been determined by DFT calculations. [Display omitted] • Thallium (I) − corannulene complexes have been proved using the ESI-MS method. • The structures of resulting complexes have been determined applying quantum chemical DFT calculations. • The interaction energies of thallium (I) − corannulene complexes have been calculated. The interaction of Tl+ cation with corannulene was investigated by using electrospray ionization mass spectrometry (ESI-MS). It was found that the thallium cation Tl+ forms with corannulene (C 20 H 10) two cationic complexes [Tl(C 20 H 10)]+ and [Tl(C 20 H 10) 2 ]+. Quantum chemical calculations proceed by density functional theory with two different functionals (B3LYP and M06-D3) provided the most probable structures of these complexes. In the energetically most favored conformation of [Tl(C 20 H 10)]+ complex, the Tl+ cation lies on the apex of pyramid which base is formed by the central pentagon of the convexly oriented corannulene molecule. In the [Tl(C 20 H 10) 2 ]+ complex the "central" cation Tl+ is situated between two molecules of the corannulene ligand. Both ligand molecules are convex to the Tl+ cation. The interaction energies, E (int), of the considered cation-π complexes [Tl(C 20 H 10)]+ and [Tl(C 20 H 10) 2 ]+ were calculated to be −121.75 and −176.98 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Selective C–H bond activation is one of the most challenging topics for organic reactions. The difficulties arise not only from the high C–H bond dissociation enthalpies but also the existence of multiple equivalent/quasi-equivalent reaction sites in organic molecules. Here, we successfully achieve the selective activation of four quasi-equivalent C–H bonds in a specially designed nitrogen-containing polycyclic hydrocarbon (N-PH). Density functional theory calculations reveal that the adsorption of N-PH on Ag(100) differentiates the activity of the four ortho C(sp3) atoms in the N-heterocycles into two groups, suggesting a selective dehydrogenation, which is demonstrated by sequential-annealing experiments of N-PH/Ag(100). Further annealing leads to the formation of N-doped graphene nanoribbons with partial corannulene motifs, realized by the C–H bond activation process. Our work provides a route of designing precursor molecules with ortho C(sp3) atom in an N-heterocycle to realize surface-induced selective dehydrogenation in quasi-equivalent sites. Selective activation of C–H bonds is a key challenge in organic reactions. Here, the authors achieve the selective activation of four quasi-equivalent C–H bonds, leading to the formation of N-doped graphene nanoribbons with partial corannulene motifs. [ABSTRACT FROM AUTHOR]

Most of the bowl‐shaped molecules are synthesized via a core‐periphery strategy with the bowl rim closed at the final stage. However, the construction of heteroatom‐doped buckybowls by the periphery‐core method with the bowl bottom sealed by inserting new atoms in the last step is quite limited. Herein we report the synthesis of a bowl‐shaped compound containing four sulfur atoms and two embedded N−B bonds with the ratio of carbon atom and heteroatom as low as four through a periphery‐core strategy. Crystallographic analysis confirms the formation of a bowl‐shaped structure. The multiple heteroatoms alter the molecular electronic structure, thus resulting in the distinct aromaticity when compared with its all‐carbon congener. The electron‐rich buckybowl shows a strong interaction with the electron‐deficient fullerene C60 by forming a 1 : 1 complex in toluene. [ABSTRACT FROM AUTHOR]

We have designed and synthesized photochromic tetrathienyl corannulene compounds, 1,2,7,8‐tetrakis(2‐methyl‐5‐phenylthiophen‐3‐yl)corannulene (1) and 1,2,7,8‐tetrakis(2,4‐dimethyl‐5‐phenylthiophen‐3‐yl)corannulene (2), by fusing two units of photochromic terarylene with a curved aromatic corannulene with a promising antenna effect. Compound 1 exhibited highly sensitive photoreactivity, with a large molar absorption coefficient of 8.2×104 M−1 cm−1 and practically photon‐quantitative photocyclization. On the other hand, a terarylene derivative with a planar aromatic phenanthrene, 9,10‐bis(2,4‐dimethyl‐5‐phenylthiophen‐3‐yl)phenanthrene (4) showed no photoreactivity. The reason for such a difference was attributed to the predominance of the photoreactive atropisomers amplified by energy migration, and the shortened distance between reactive carbons induced by the curved structure. [ABSTRACT FROM AUTHOR]

Some years ago, Jishan Wu reported the synthesis of 8MC and 10MC, two homologues of the cyclopenta-ring-fused oligo(m-phenylene) macrocycles mMC, each behaving as an annulene-within-an-annulene (AWA). This was a surprising result as the AWA behavior is rare. Both molecules have a partial polyradical character, enforced by the quest for restoring some aromatic character of benzene rings. However, that restoration brings back some coupling between the two annulenes. Indeed, we found that the geometry and the magnetically induced currents indicate that, while 8MC does have an AWA character, this is not the case of the larger 10MC. Limitations of the design strategy of AWA molecules should be taken into account in future attempts to prepare novel large coronenes., (© 2024 Wiley-VCH GmbH.)

Bonding and aromaticity in the bowl-shaped C5v and planar D5h geometries of corannulene and the planar D6h geometry of coronene are investigated using 3D isosurfaces and 2D contour plots of the isotropic magnetic shielding σiso(r) and, for planar geometries, of the out-of-plane component of the shielding tensor σzz(r). Corannulene and coronene both feature conjoined shielded “doughnuts” around a peripheral six-membered carbon ring, suggesting strong bonding interactions and aromatic stability; a deshielded region inside the hub ring of corannulene indicates that this ring is antiaromatic, more so in planar corannulene. The switch from the planar to the bowl-shaped geometry of corannulene is shown to enhance both bonding and the local aromaticities of the five- and six-membered rings; these factors, in addition to ring strain reduction, favour the bowl-shaped geometry. The most and least shielded bonds in both corannulene and coronene turn out to be the spoke and hub bonds, respectively. The higher π electron activity over spoke bonds in planar corannulene and coronene is supported by σzz(r) contour plots in planes 1 Å above the respective molecular planes; these findings about spoke bonds are somewhat unexpected, given that ring current studies indicate next to no currents over spoke bonds.

The dynamic and static nature of the XH-∗-π and YX-∗-π (X = F, Cl, Br, and I; Y = X and F) interactions in the distorted π-system of corannulene (π(C20H10)) is elucidated with a QTAIM dual functional analysis (QTAIM-DFA), where asterisks emphasize the presence of bond critical points (BCPs) on the interactions. The static and dynamic nature originates from the data of the fully optimized and perturbed structures, respectively, in QTAIM-DFA. On the convex side, H in F–H-∗-π(C20H10) and each X in Y–X-∗-π(C20H10) join to C of the central five-membered ring in π(C20H10) through a bond path (BP), while each H in X–H-∗-π(C20H10) does so to the midpoint of C=C in the central five-membered ring for X = Cl, Br, or I. On the concave side, each X in F–X-∗-π(C20H10) also joins to C of the central five-membered ring with a BP for X = H, Cl, Br, and I; however, the interactions in other adducts are more complex than those on the convex side. Both H and X in X–H-∗-π(C20H10) (X = Cl and Br) and both Fs in F–F-∗-π(C20H10) connect to the three C atoms in each central five-membered ring (with three BPs). Two, three, and five BPs were detected for the Cl–Cl, I–H, Br–Br, and I–I adducts, where some BPs do not stay on the central five-membered ring in π(C20H10). The interactions are predicted to have a vdW to CT-MC nature. The interactions on the concave side seem weaker than those on the convex side for X–H-∗-π(C20H10), whereas the inverse trend is observed for Y–X-∗-π(C20H10) as a whole. The nature of the interactions in the π(C20H10) adducts of the convex and concave sides is examined in more detail, employing the adducts with X–H and F–X placed on their molecular axis together with the π(C24H12) and π(C6H6) adducts.

The high-regioselective synthesis of bisadducts based on low-symmetry C70 has been a challenging work due to the large amount of formed regioisomers, which require tedious separation procedures for isomeric purity and block their application in different fields. Herein, we successfully obtained a novel 1, 2, 3, 4-bis(triazolino)fullerene[C70] 2 with high regioselectivity by the rigid tether-directed regioselective synthesis strategy and the corresponding molecular structure was unambiguously confirmed by single-crystal X-ray crystallography characterization. The crystal data clearly show that the addition occurs at the domain of corannulene moiety at the end of ellipse C70 as well as the 1, 2, 3, 4-addition sites located at one hexagonal ring with a [6,6]-closed addition pattern. Furthermore, 2 was applied as an additive of perovskite layer to construct MAPbI3-based regular (n-i-p) perovskite solar cells, affording the power conversion efficiency (PCE) of 18.59%, which is a 7% enhancement relative to that of control devices without additive. [ABSTRACT FROM AUTHOR]

The corannulene pincer (also known in the literature as the buckycatcher) is a fascinating system that may encapsulate, among other molecules, the C 60 and C 70 fullerenes. These complexes are held together by strong π-stacking interactions. Although these are quantum mechanical effects, their description by quantum chemical methods has proved very hard. We used three semi-empirical methods, PM6-D3H4X, PM6-D3H+ and GFN2-xTB, to model the interactions. Binding to fullerenes was extended to all open conformations of the buckycatcher, and with the proper choice of solvation model and partition functions, we obtained Gibbs free energies of binding that deviated by 1.0–1.5 kcal/mol from the experimental data. Adding three-body dispersion to PM6-D3H+ led to even better agreement. These results agree better with the experimental data than calculations using higher-level methods at a significantly lower fraction of the computational cost. Furthermore, the formation of adducts with C 60 was studied using dynamical simulations, which helped to build a more complete picture of the behavior of the corannulene pincer with fullerenes. We also investigated the use of exchange-binding models to recover more information on this system in solution. Though the final Gibbs free energies in solution were worsened, gas-phase enthalpies and entropies better mirrored the experimental data. [ABSTRACT FROM AUTHOR]