Excited State Polarizability of Some Polycyclic Polyenes

2017 ◽  
Vol 68 (2) ◽  
pp. 307-310 ◽  
Author(s):  
Ana Maria Ciubara ◽  
Andreea Celia Benchea ◽  
Carmen Beatrice Zelinschi ◽  
Dana Ortansa Dorohoi
Keyword(s):  
Excited State ◽  
Absorption Spectra ◽  
Excited States ◽  
Electronic Absorption ◽  
Ground State ◽  
Electronic Absorption Spectra ◽  
Photon Absorption ◽  
Absorption Process ◽  
Polar Solvents ◽  
Molecular Parameters

The electronic absorption spectra of five polycyclic polyenes were recorded in non-polar solvents in order to determine their polarizability in excited states from the strength of the dispersive interactions in their diluted solutions. The bathochromic shifts of p-p* vibronic bands prove the increase of the molecular polarizabilty in the photon absorption process. Some molecular parameters of the analyzed polyenes in their ground state were computed by using the programs from Spartan�14.

THE ELECTRONIC ABSORPTION SPECTRA OF DIXANTHOGENS

1961 ◽  
Vol 39 (12) ◽  
pp. 2590-2592 ◽  
Author(s):  
M. L. Shankaranarayana ◽  
C. C. Patel
Keyword(s):  
Absorption Spectra ◽  
Electronic Absorption ◽  
High Intensity ◽  
Electronic Absorption Spectra ◽  
Blue Shift ◽  
Polar Solvents ◽  
Low Intensity

The electronic absorption spectra of diethyl, diisopropyl, di-n-butyl, and diisoamyl dixanthogens have been studied in polar and non-polar solvents. The compounds exhibit a low-intensity band around 365 mµ and two high-intensity bands around 285 and 242 mµ. The 365 mµ band is assigned, as a result of the solvent studies, to n → π* transition and the 285 mµ band to π → π* transition. The band around 242 mµ may be due to the n → σ* transition, since in polar solvents it shows mainly a blue shift.

Spectra of the 1:1 and 3:1 solid complexes of coronene-TCNQ

1977 ◽  
Vol 55 (21) ◽  
pp. 3712-3716 ◽  
Author(s):  
Kim Doan Truong ◽  
André D. Bandrauk
Keyword(s):  
Charge Transfer ◽  
Absorption Spectra ◽  
Electronic Absorption ◽  
Ground State ◽  
Electronic Absorption Spectra ◽  
Charge Transfer Band ◽  
Out Of Plane ◽  
The Individual ◽  
A Charge ◽  
Solid Complexes

Two new solid TCNQ complexes have been isolated, coronene–TCNQ 1:1 and 3:1. The infrared and electronic absorption spectra are presented for the two different stoichiometries. From these spectra we infer that the complexes are covalent in the ground state with a charge transfer band appearing at 730 nm. The out of plane vibrations of the individual molecules are noticeably perturbed upon complexation.

Reproduction of the UV-vis spectra of boron subphthalocyanine chloride in different solvents using time-dependent generalized Kohn–Sham density functionals with first solvation shell

2018 ◽  
Vol 22 (08) ◽  
pp. 670-678 ◽  
Author(s):  
Xue Chen ◽  
Wenlan Chen ◽  
Shaohui Zheng
Keyword(s):  
Absorption Spectra ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Solvation Shell ◽  
Photon Absorption ◽  
Ultraviolet Region ◽  
Density Functionals ◽  
Research Fields ◽  
Boron Subphthalocyanine ◽  
Experimental Absorption

Because of the unique physical, chemical and optical characteristics of boron subphthalocyanine chloride, it has been widely applied in different research fields and attracted global researchers. Deep insight into its UV-vis spectrum is required to understand the mechanism of the photon absorption of boron subphthalocyanine chloride in its condensed phase. In the present work, we utilize generalized Kohn–Sham density functionals with a non-equilibrium solvation model to simulate the UV-vis spectra of boron subphthalocyanine chloride in different solvents. Without considering the first solvation shell, we find that the slopes of lines drawn with [Formula: see text]B97XD and CAM-B3LYP results vs. experimental absorption wavelengths are close to 1.0 and root–mean–square deviations are less than 40 nm. We also find that the inclusion of the first solvation shell surrounding boron subphthalocyanine chloride monomers generally makes the calculated results worse. Finally, we discover that the simulated results overestimate oscillator strength of electronic absorption spectra in the ultraviolet region with respect to experimental spectra. These results imply that it may be important to consider the aggregation of solute molecules in order to understand the electronic absorption spectra of subPC in solution

Molecular interactions in the spectra of diaza-aromatics

1974 ◽  
Vol 27 (8) ◽  
pp. 1613 ◽  
Author(s):  
JR Honner ◽  
PR Nott ◽  
BK Selinger
Keyword(s):  
Hydrogen Bonding ◽  
Absorption Spectra ◽  
Molecular Interactions ◽  
Electronic Absorption ◽  
Low Temperatures ◽  
Electronic Absorption Spectra ◽  
Polar Solvents ◽  
Hydrogen Bonding Interactions ◽  
Low Concentrations

A reported variation of the electronic absorption spectra of diaza-aromatics in non-polar solvents with temperature appears to be explicable in terms of three effects. Hydrogen bonding interactions occur in all but exhaustively dried non-polar solvents. Microcrystals form readily at low temperatures at even quite low concentrations (c. 10-5M). The solutions are sensitive to exposure to light. The diaza-aromatics undergo photochemical change forming, in some cases, photoadducts with the solvent.

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