Metal halide perovskites have been successfully applied in a variety of fields such as LEDs, lasers and solar cells, thanks to their excellent optoelectronic properties. Capillary fibers can further expand the range of perovskite applications and at the same time improve its stability by encapsulating the perovskite inside the capillary. However, the high-quality perovskite film-coated […]
This paper reports on the synthesis and characterization of original sodium calcium silicate glass, with CaF2 as a nucleating agent, along with the successful transformation of the as-made matrix into glass-ceramic. Characteristic temperatures of thermal events were investigated by Differential Thermal Analysis. Volumetric density, refractive index, molar volume, and electronic polarizability of the newly developed glasses […]
The UV-induced photochemistry and molecular structure of 3-aminopyrazine-2-carboxylic acid were studied in argon matrices by Fourier-transform infrared spectroscopy and B3LYP/6-311++G(2d,2p) calculations. Out of seventeen possible isomers of this molecule located on the singlet potential energy surface the most stable one, APA1 comprising intramolecular O–H···N and N–H···O hydrogen bonds, was detected experimentally in the matrix after […]
The nitrile imine-mediated tetrazole–ene cycloaddition is a widely used class of photoligation. Optimizing the reaction outcome requires detailed knowledge of the tetrazole photoactivation profile, which can only partially be ascertained from absorption spectroscopy, or otherwise involves laborious reaction monitoring in solution. Photodissociation action spectroscopy (PDAS) combines the advantages of optical spectroscopy and mass spectrometry in […]
We prepared a series of meso-thienyl boron-dipyrromethene (Bodipy) derivatives to investigate the spin–orbit charge transfer intersystem crossing (SOCT-ISC). The photophysical properties of the compounds were studied by steady-state and femtosecond/nanosecond transient absorption spectroscopy, as well as density functional theory (DFT) computations. Different from the meso-phenyl Bodipy analogues, the meso-thienyl Bodipy are weakly fluorescent. Based on femtosecond transient absorption […]
Photosynthetic integral membrane reaction center (RC) proteins capture and convert sunlight into chemical energy via efficient charge separation achieved through a series of rapid, photoinitiated electron transfer steps. These fast electron transfers create an entangled spin qubit (radical) pair that contains detailed information about the weak magnetic interactions, structure, and dynamics of localized protein environments […]
Spiro rhodamine (Rho)-perylene (Pery) electron donor–acceptor dyads were prepared to study the spin–orbit charge transfer intersystem crossing (SOCT-ISC) in these rigid and sterically congested molecular systems. The electron-donor Rho (lactam form) moiety is attached via the N–C bond to the electron acceptor at either 1- or 3-position of the Pery moiety (Rho-Pery-1 and Rho-Pery-3). Severe torsion of […]
The main objective of multi-fluorophoric sample spectroscopy is to find the relative concentrations of individual components. If the spectra of fluorophores have broad complex shapes and significantly overlap, direct analysis is not possible. For various reasons, regression to model spectra attributed to known substances might not be easy either. Here, we describe a method of […]
A low-cost adjustable illumination scheme for hand-held photoacoustic imaging probe is presented, manufactured and tested in this paper. Compared with traditional photoacoustic probe design, it has the following advantages: (1) Different excitation modes can be selected as needed. By tuning control parameters, it can achieve bright-field, dark-field, and hybrid field light illumination schemes. (2) The […]
Photoacoustic imaging is a promising technique to provide guidance during multiple surgeries and procedures. One challenge with this technique is that major blood vessels in the liver are difficult to differentiate from surrounding tissue within current safety limits, which only exist for human skin and eyes. In this paper, we investigate the safety of raising […]