Simultaneous Detection of Circularly Polarized Luminescence and Raman Optical Activity in an Organic Molecular Lemniscate

Benzo-Extended Heli(aminoborane)s: Inner Rim BN-Doped Helical Molecular Carbons with Remarkable Chiroptical Properties

Atomically precise synthesis of three-dimensional boron-nitrogen (BN)-based helical structures constitutes an undeveloped field with challenges in synthetic chemistry. Herein, we synthesized and comprehensively characterized a new class of helical molecular carbons, named benzo-extended [n]heli(aminoborane)s ([n]HABs), in which the helical structures consisted of n = 8 and n = 10 ortho-condensed conjugated rings with alternating BN atoms at the inner rims. X-ray crystallographic analysis, photophysical studies, and density functional theory calculations revealed the unique characteristics of this novel [n]HAB system. Owing to the high enantiomerization energy barriers, the optical resolution of [8]HAB and [10]HAB was achieved with chiral high-performance liquid chromatography. The isolated enantiomers of [10]HAB exhibited record absorption and luminescence dissymmetry factors (|gabs|=0.061; |glum|=0.048), and boosted CPL brightness up to 292 M-1 cm-1, surpassing most helicene derivatives, demonstrating that the introduction of BN atoms into the inner positions of helicenes can increase both the |gabs| and |glum| values.

Host-Guest Chemistry in Binary and Ternary Complexes Utilizing π-Conjugated Carbon Nanorings

The carbon nanorings, possessing a radial π system, have garnered significant attention primarily due to their size-dependent photophysical properties and the presence of a unique curved π-conjugated cavity. This is evidenced by the rapid proliferation of publications. Furthermore, the integration of building blocks into CPP skeletons can confer [n]CPPs with novel and exceptional photophysical and electronic characteristics, as well as chiral properties and host-guest interactions, thereby augmenting the diversity of [n]CPPs. Notably, the curved π surface structures and concave cavity of carbon nanorings enable them to host aromatic or non-aromatic guests with a complementarily curved surface, resulting in interesting binary or ternary complexes. This review provides a comprehensive treatment of literature reports on binary and ternary complexes, focusing on both their host-guest interactions and properties. It is important to note that the scope of this review is limited to host-guest chemistry in binary and ternary complexes based on π-conjugated carbon nanorings.

Quantum Modification of Indacenodithieno[3,2-b]thiophene-Based Non-fullerene Acceptor Molecules for Organic Solar Cells of High Efficiency

In order to enhance the efficacy of organic solar cells, six new three-dimensional small donor molecules (IT-SM1 to IT-SM6) have been computationally designed by modifying the peripheral acceptors of the reference molecule (IT-SMR). The frontier molecular orbitals revealed that IT-SM2 to IT-SM5 had a smaller band gap (E_gap) than IT-SMR. They also had smaller excitation energies (E_x) and exhibited a bathochromic shift in their absorption maxima (λ_max) when compared to IT-SMR. In both the gas and chloroform phases, IT-SM2 had the largest dipole moment. IT-SM2 also had the best electron mobility, while IT-SM6 had the best hole mobility owing to their smallest reorganization energy for electron (0.1127 eV) and hole (0.0907 eV) mobility, respectively. The analyzed donor molecules' open-circuit voltage (V_OC) indicated that all of these proposed molecules had greater V_OC and fill factor (FF) values than the IT-SMR molecule. In accordance with the evidence of this work, the altered molecules can seem to be quite proficient for usage by experimentalists and have prospective use in future in the manufacture of organic solar cells with improved photovoltaic properties.

A Fourfold Gold(I)-Aryl Macrocycle with Hyperbolic Geometry and its Reductive Elimination to a Carbon Nanoring Host

An ethylene glycol-decorated [6]cyclo-meta-phenylene (CMP) macrocycle was synthesized and utilized as a subunit to construct a fourfold Au^I ₂ -aryl metallacycle with an overall square arrangement. The corners consist of rigid dinuclear gold(I) complexes previously known to form only triangular metallacycles. The interplay between the conformational flexibility of the [6]CMP macrocycle and the rigid dinuclear gold(I) moieties enable the square geometry, as revealed by single-crystal X-ray diffraction. The formation of the gold complex shows size-selectivity compared to an alternative route using platinum(II) corner motifs. Upon reductive elimination, an all-organic ether-decorated carbon nanoring was obtained. Investigation as a host for the complexation of large guest molecules with a suitable convex π-surfaces was accomplished using isothermal NMR binding titrations. Association constants for [6]cycloparaphenylene ([6]CPP), [7]CPP, C₆₀ , and C₇₀ were determined.

Novel A-π-D-π-A type non-fullerene acceptors of dithienyl diketopyrropopyrrole derivatives to enhance organic photovoltaic applications: a DFT study

To boost the photovoltaic attributes of organic photovoltaic cells, seven dithienyl diketopyrropopyrrole (TDPP) donor-based A-π-D-π-A (acceptor-bridge-donor-bridge-acceptor) type molecules (TM1-TM7) were formulated by modifying the electron accepting ends of the reference molecule (TMR). Optical and quantum chemical parameters of seven synthesized molecules were investigated using density functional theory with the MPW1PW91/6-31G(d,p) functional. Several parameters that can be used to measure and improve the efficiency of solar cells have been analyzed and summed up. These parameters include binding energy of exciton, excitation energy of electron, reorganization energies, dipole moment, molecular electrostatic potential, charge mobility, wavelength of maximum absorption, open circuit voltage, short circuit current, fill factor, density of states, transition density matrices, as well as iso-surface and non-covalent interactions. Thus, all of our proposed structures are perceived to be superior to the reference in terms of the maximum possible solar energy yield in solar cells with bulk heterojunctions, as determined by analyses of our designed molecules for the aforementioned parameters.