Polarity and strong sensitivity to external electric field in azacrown oligophenylenevinylene.

Spectrochim Acta A Mol Biomol Spectrosc

Department of Physics, Pomeranian University of Słupsk, Słupsk 76-200 Poland. Electronic address:

Published: April 2022

Complex study of quadrupolar azacrown dye (E,E)-5,5́-Bis[2-(4-(4',7',10',13',16'-pentaoxa-1 azacyclooctadecyl)phenyl)ethenyl]-2,2́-bipyridine 1 was performed. Electronic spectra of absorption and fluorescence in different solvents exhibit strong solvatochromism. Electrooptical absorption measurements (EOAM) were performed to determine the electric dipole moments. These measurements gave large values of dipole moments in the ground μ and Franck-Condon excited state μ equal to 6.8 ± 0.14C m and 39.3 ± 0.3C m, respectively. Furthermore, the results of EOAM suggest the existence two conformers in the ground state with close energies of electronic transitions. Density functional theory (DFT) calculations directly show that the shape of this molecule is not planar in the ground state and also allows the existence of two stable conformers with close energies. They appeared due to different orientations of the left and right pyridine fragments of the solute. The energies, electric dipole moments and dependences of dipole moments on the strength of applied electric field were calculated for found stable conformers of 1. DFT calculations with TD / B3LYP / 3-21G and cc-pVDZ (Time Depend) approach show that external electric field increases dramatically the dipole moments of the solute under study. The higher field intensity the larger the excited electric dipole in the range intensities from zero to ∼ 2.8·× 10 V/m.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.saa.2021.120824DOI Listing

Publication Analysis

Top Keywords

dipole moments
20
electric field
12
electric dipole
12
external electric
8
ground state
8
close energies
8
dft calculations
8
stable conformers
8
electric
6
dipole
6

Similar Publications

Novel organic additives with high dipole moments: Improving the anode interface structure to enhance the performance of zinc ion aqueous batteries.

J Colloid Interface Sci

December 2024

Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou, Fujian 350002, PR China; Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian 350108, PR China; Fujian College, University of Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China. Electronic address:

The reversibility and stability of aqueous zinc-ion batteries (AZIBs) are largely limited by free-water-induced side reactions (e.g., hydrogen evolution and zinc corrosion) and negative zinc dendrite growth.

View Article and Find Full Text PDF

The dielectric behavior of Asparagine (CHNO) in water over the frequency range of 10 MHz to 30 GHz in the temperature region of 278.15-303.15 K in a step of 5 K has been carried out using time domain reflectometry (TDR) at various concentrations of asparagine.

View Article and Find Full Text PDF

High-Performance Circular Polarization Multiple-Resonance TADF Molecules with Enhanced Long-Range Charge Transfer Based on Chiral Paracyclophane.

J Phys Chem Lett

December 2024

State Key Laboratory of Organic Electronics and Information Displays, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, P. R. China.

Circularly polarized multiple-resonance thermally activated delayed fluorescence (CP-MR-TADF) materials have received widespread attention in recent years, but it remains a formidable challenge to design high-performance CP-MR-TADF emitters concurrently exhibiting high quantum efficiency, narrowband emission, and high dissymmetry factor (). Here, we perform an in-depth theoretical investigation on the CP-MR-TADF materials based on [2.2] paracyclophane (pCp) derivatives.

View Article and Find Full Text PDF

Spectroscopy and Dynamics of the Dipole-Bound States of -, -, and -Methylphenolate Anions.

J Phys Chem A

December 2024

Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.

A photodetachment and photoelectron spectroscopic study by employing a cryogenically cooled ion trap combined with a velocity-map imaging setup has been carried out to unravel the vibrational structures and autodetachment dynamics of the dipole-bound states (DBSs) of -, -, and -methylphenolate anions (-, -, and -CHPhO). The electron binding energy of the DBS increases monotonically with the increase of the neutral dipole moment to give respective values of 66 ± 15, 123 ± 18, or 154 ± 14 cm for the -, -, or -isomer. The different electron-donating effects of the methyl moieties in the three geometrically different isomers seem to be reflected in the experiment.

View Article and Find Full Text PDF

Cisplatin-based platinum compounds are important clinical chemotherapeutic agents that participate in most tumor chemotherapy regimens. Through density-functional theory calculations, the formation and stability of the inorganic oxide carrier, the mechanisms of the hydrolysis reaction of the activated platinum compound, and its binding mechanism with DNA bases can be studied. The higher the oxidation state of Pt (II to IV), the more electrons transfer from the magnesia-gold composite material to the platinum compound.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!