Optical properties of polar push–pull chromophore (diphenylpolyene with donor/acceptor terminal substituents) are studied using hybrid time-dependent density functional theory (TD-DFT). The optical transitions are thoroughly examined. This includes oneand two-photon absorption, and fluorescence, as a function of the underlying density functional, the basis set choice, and the solvent. Calculate...

Long-range corrected hybrids represent an increasingly popular class of functionals for density functional theory (DFT) that have proven to be very successful for a wide range of chemical applications. In this Communication, we examine the performance of these functionals for time-dependent (TD)DFT descriptions of triplet excited states. Our results reveal that the triplet energies are particul...

A quantum-chemical study on the consequences of geometric modification and chelation on the electronic structure and optical properties of a tetra(carboxylic acid)phenyleneethynylene dye, of interest for chemical sensing applications, is presented. Rotation within the central biphenylene and complexation with divalent metal ions--in particular Cu2+--lead to notable changes in the absorption and...

Understanding first-principles energy transport in organic molecules reveals novel energy harvesting systems, quantum computing, and solar power energy transportation and production. DiSC2(5), also named Cy5, exhibits bright fluorescence signals and has shown promising lossless exciton transport properties, as well as tunable energy absorption and emission when conjoined with DNA. This paper fo...

7,9-Dibromobenzo[h]quinolin-10-ol (1), a benzo[h]quinolin-10-ol derivative, was synthesized and characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic space group P21/n, with a = 3.9573(4), b = 18.0416(18), c = 15.8210(16) Å, α = 90◦, β = 96.139(3)◦, and γ = 90◦. Compound 1 exhibits an intramolecular six-membered-ring hydrogen bond, from which excited-state intramo...

The all-boron fullerenes B40(-1) and B39(-1) discovered in recent experiments are characterized and revealed using photoelectron spectroscopy. Except for the photoelectron spectroscopy, one may identify such boron clusters with other spectroscopic techniques, such as infrared spectra and Raman spectra. Insight into the spectral properties of boron clusters is important to understand the boron c...

Our density functional theory (DFT)/time-dependent DFT calculations for the fluoride anion sensor, 5,7-dibromo-8-tert-butyldimethylsilyloxy-2-methylquinoline (DBM), suggested a different sensing mechanism from the experimentally proposed one (Chem. Commun., 2011, 47, 7098). Instead of the formation of fluoride-hydrogen-bond complex (DBMOHF) and excited-state proton transfer mechanism, the theor...

It is demonstrated that time-dependent density functional theory (DFT) calculations can accurately predict changes in near-UV electronic circular dichroism (ECD) spectra of DNA as the structure is altered from the linear (free) B-DNA form to the supercoiled N-DNA form found in nucleosome core particles. At the DFT/B3LYP level of theory, the ECD signal response is reduced by a factor of 6.7 in g...

In this work we investigated by density functional theory (DFT)/time-dependent DFT (TDDFT) supramolecular complexes for photoinitiated electron collection, in particular [{(bpy)2Ru(dpp)}2RhCl2] and related catalysts derived by variation of the ligand/metal. The electron collection in this class of catalysts enables hydrogen production or DNA cleavage, among other applications. Changes in excita...

Donor-acceptor Stenhouse adducts (DASAs) are a very recent class of organic photoswitches that combine excellent properties, such as color and polarity change, a large structural modification, and excellent fatigue resistance. Despite their potential applications in different fields, very few studies have focused on rationalizing their electronic structure properties. Here, by means of differen...