Spiro donor–acceptor TADF emitters: naked TADF free from inhomogeneity caused by donor acceptor bridge bond disorder. Fast rISC and invariant photophysics in solid state hosts

The molecular photophysics of 10-phenyl-10H,10′H-spiro[acridine-9,9′-anthracen]-10′-one (ACRSA) are used as an ideal molecule to probe how external factors affect the TADF and rISC mechanisms.

Highly Sensitive and Selective Fluorescent Sensor for Ag+ in Using β-Cyclodextrin / Chitosan Polymer Coated S QDs Based on Aggregation Caused Quenching Mechanism

A fluorometric sensor based on poly (β- cyclodextrin/chitosan) with H bonded S QDs/CTSCD nanocomposites was synthesized by self-assembly. They were characterized by FTIR, UV–Vis spectroscopy, XPS, and TEM. The S QDs on the chain of the polymer could coordinate with transition-metal ions due to surface electronegativity. The distance between the S QDs on the different chains of polymer could construct the bridge bond of S–Ag+–S with silver ions leading to fluorescence aggregation-caused quenching. The linear range of the method was from 1.0×10-5 -5.5×10−5mol/L. The correlation coefficient was 0.9992 with a detection limit of 66.7 nM. This method could be used to detect silver ions in real samples with excellent sensitivity and selectivity, indicating its potential as a novel sensor.

DIMERIZATION OF POLYAROMATIC HYDROCARBON MOLECULES WITH FORMATION OF E-BRIDGE BOND: A THEORETICAL STUDY

In combustion engines and other fuel-burning devices, during the combustion of hydrocarbon fuels at a temperature of 1000-1400 K, soot is actively formed, deposited on the cold surfaces of the devices, which reduces their service life. At present, much attention is paid to the problems of controlling the amount and size of soot particles formed during combustion. However, the mechanism of soot formation has not yet been fully understood. It is assumed that under combustion conditions, young soot particles are formed by nucleation of aromatic and polyaromatic hydrocarbons (PAHs) with subsequent growth of particles due to the addition of new molecules.

Halogen bond shortens and strengthens the bridge bond of [1.1.1]propellane and the open form of [2.2.2]propellane

The electron scavenger property of halogen bond donors is employed to stabilize the bridge-bond of [1.1.1]propellane and o-[2.2.2]propellane.