Theoretical study of chemosensor for fluoride anion and optical properties of the derivatives of diketopyrrolopyrrole

Gating That Suppresses Charge Recombination-The Role of Mono-N-Arylated Diketopyrrolopyrrole

Suppressing the charge recombination (CR) that follows an efficient charge separation (CS) is of key importance for energy, electronics, and photonics applications. We focus on the role of dynamic gating for impeding CR in a molecular rotor, comprising an electron donor and acceptor directly linked via a single bond. The media viscosity has an unusual dual effect on the dynamics of CS and CR in this dyad. For solvents with intermediate viscosity, CR is 1.5-3 times slower than CS. Lowering the viscosity below ∼0.6 mPa s or increasing it above ∼10 mPa s makes CR 10-30 times slower than CS. Ring rotation around the donor-acceptor bond can account only for the trends observed for nonviscous solvents. Media viscosity, however, affects not only torsional but also vibrational modes. Suppressing predominantly slow vibrational modes by viscous solvents can impact the rates of CS and CR to a different extent. That is, an increase in the viscosity can plausibly suppress modes that are involved in the transition from the charge-transfer (CT) to the ground state, i.e., CR, but at the same time are not important for the transition from the locally excited to the CT state, i.e., CS. These results provide a unique example of synergy between torsional and vibronic modes and their drastic effects on charge-transfer dynamics, thus setting paradigms for controlling CS and CR.

Theoretical study of the optical and charge transport properties of π-conjugated three-coordinate organoboron compounds as organic light-emitting diodes materials

A series of π-conjugated three-coordinate organoboron compounds have been designed as luminescent and charge transport materials for OLEDs application.

Rational design of organoboron heteroarene derivatives as luminescent and charge transport materials for organic light-emitting diodes

A series of organoboron heteroarene derivatives have been designed as luminescent and charge transport materials for OLEDs application.

Rational design of organoboron derivatives as chemosensors for fluoride and cyanide anions and charge transport and luminescent materials for organic light-emitting diodes

The interactions between chemosensors, donor-π-acceptor (D-π-A) dipolar organoboron derivatives, and different (CN⁻, F⁻, Cl⁻, and Br⁻) anions have been theoretically investigated using DFT approaches. Theoretical investigations have been performed to explore the optical, electronic, charge transport, and stability properties of organoboron derivatives as charge transport and luminescent materials for organic light emitting devices (OLEDs). It turned out that the unique selectivity of organoboron derivatives for F⁻/CN⁻ is ascribed to the formation of chemosensors complexes. The frontier molecular orbitals (FMOs) and local density of states analysis have turned out that the vertical electronic transitions of absorption and emission for chemosensors and their F⁻/CN⁻ complexes are characterized as intramolecular charge transfer (ICT). The formation of complexes has effect on the distribution of FMOs and the flowing direction of electronic density for vertical transition. The study of substituent effects suggests that the derivatives with thiophene (2), furan (3), and 1H-pyrrole (4) fragments, are expected to be promising candidates for ratiometric fluorescent fluoride and cyanide chemosensors as well as chromogenic chemosensors, whereas derivatives with pyridine (5) and pyrimidine (6) fragments can serve as chromogenic chemosensors only. Furthermore, all the derivatives are promising luminescent and hole transport materials and 2, 3, 5, and 6 can serve as electron transport materials for OLEDs.

A highly selective colorimetric and ratiometric fluorescent chemodosimeter for detection of fluoride ions based on 1,8-naphthalimide derivatives

A high selective colorimetric and ratiometric fluorescent probe based on 4-hydroxy-1, 8-naphthalimide was designed and synthesized to detect fluoride ions (F(-)). The sensing behavior of this probe was studied by UV-visible and fluorescence spectroscopy. The probe displays an 110 nm red-shift of fluorescence emission and the color changes from colorless to yellow by virtue of the strong affinity of F(-) toward silicon which can act as a new visual sensor for F(-).

Supramolecular analyte recognition: experiment and theory interplay

Synergy of experimental and theoretical tools has made significant impact in the assessment of supramolecular recognition of analytes of relevance to biology and the environment.