Macrocyclic Bridgehead Fluorophores, Pyrrolyl-diazabicyclo[8.3.1]tetradecadienones, with Giant Stokes Shifts.

A previously unknown class of fluorophores was discovered, which represents 14-membered bridgehead heterocycles, pyrrolyl-diazabicyclo[8.3.1]tetradecadienones, herein referred to as PY-14-ONEs.

Nonlinear Absorption and Refraction of Picosecond and Femtosecond Pulses in HgTe Quantum Dot Films.

We report measurements of the saturated intensities, saturable absorption, and nonlinear refraction in 70-nm thick films containing 4 nm HgTe quantum dots. We demonstrate strong nonlinear refraction and saturable absorption in the thin films using tunable picosecond and femtosecond pulses. Studies were carried out using tunable laser pulses in the range of 400-1100 nm.

Oxidative C-H/C-H Coupling of Dipyrromethanes with Azines by TiO-Based Photocatalytic System. Synthesis of New BODIPY Dyes and Their Photophysical and Electrochemical Properties.

Oxidative C-H/C-H coupling reactions of dipyrromethanes with azines in the presence of a heterophase oxidative photocatalytic system (O/TiO/visible light irradiation) were carried out. As a result of cyclization of obtained compounds with boron trifluoride etherate, new hetaryl-containing derivatives of 4,4-difluoro-4-boron-3,4-diaza--indacene were synthesized. For the obtained compounds, absorption and luminescence spectra, quantum yields of luminescence as well as cyclic volt-amperograms were measured.

Synthesis and low-order optical nonlinearities of colloidal HgSe quantum dots in the visible and near infrared ranges.

We synthesize colloidal HgSe quantum dots and characterize their nonlinear refraction and nonlinear absorption using a Nd:YAG laser and its second harmonic. The 7.5 nm quantum dots were synthesized using the hot-injection method.

Nonlinear Optical Characterization of InP@ZnS Core-Shell Colloidal Quantum Dots Using 532 nm, 10 ns Pulses.

InP@ZnS core-shell colloidal quantum dots (CQDs) were synthesized and characterized using the z-scan technique. The nonlinear refraction and nonlinear absorption coefficients ( = -2 × 10 cm W, = 4 × 10 cm W) of these CQDs were determined using 10 ns, 532 nm pulses. The saturable absorption ( = -1.