Calculation of the electronic spectrum within the CNDO/S (complete neglect of differential overlap/S) approximation and character of the long-wave absorption band of 2-N-pyridinia-1,3-indandione betaine

1981 ◽  
Vol 17 (5) ◽  
pp. 483-486
Author(s):  
V. �. Kampar ◽  
Z. P. Bruvers ◽  
O. Ya. Neiland
Keyword(s):  
Absorption Band ◽  
Electronic Spectrum ◽  
Wave Absorption ◽  
Long Wave ◽  
Complete Neglect ◽  
Neglect Of Differential Overlap

Oscillator strength of the long-wave absorption band and inhibition activity of some hydrogenated quinolines

1967 ◽  
Vol 6 (4) ◽  
pp. 360-362
Author(s):  
R. P. Vorob'eva ◽  
L. P. Zalukaev ◽  
E. N. Ivanova
Keyword(s):  
Absorption Band ◽  
Oscillator Strength ◽  
Inhibition Activity ◽  
Wave Absorption ◽  
Long Wave

The Structure of Polyisoprenes. V. Ultraviolet Absorption Spectra of Certain Carbalkoxy-Substituted 1,5-Dienes, and the Charge-Resonance Spectra of Glutaconic Ester Enolate Ions

1946 ◽  
Vol 19 (1) ◽  
pp. 23-33
Author(s):  
L. Bateman ◽  
H. P. Koch
Keyword(s):  
Absorption Band ◽  
Absorption Spectra ◽  
Special Interest ◽  
Crystalline State ◽  
Marked Change ◽  
Cyanine Dyes ◽  
Structural Type ◽  
Wave Absorption ◽  
Long Wave ◽  
Ester Enolate

Abstract Spectral evidence supports the conclusion reached in Part IV that ring-chain mesomerism in methyl and ethyl Δ1,5-hexadiene-l,1,3,3,4,4,6,6-octacarboxylates is nonexistent in solution, just as in the crystalline state. The data are not inconsistent with chain hyperconjugation in these molecules. The marked change in structural type that follows the addition of one molecule of hydrogen or hydrolytic reagent has been verified spectrographically. The spectra of methyl and ethyl α,γ-dicarboxyglutaconic esters and their sodium and cupric derivatives have been measured in various solvents, and their tautomeric behavior compared with that of other keto-enols. Of special interest is the intense long-wave absorption band of the enolate ions, which are recognized as simple structural analogs of the cyanine dyes giving rise to similar charge-resonance spectra. A preliminary comment is made on the present accepted structure of ethyl 6-ethoxy-α-pyrone-3:5-dicarboxylate.

On the Determination of Transition-Moment Directions from Absorption Anisotropy Measurements

1987 ◽  
Vol 42 (6) ◽  
pp. 617-621 ◽  
Author(s):  
A. Kawski ◽  
Z. Gryczyński
Keyword(s):  
Absorption Band ◽  
Polymer Film ◽  
Stretch Ratio ◽  
Transition Moment ◽  
Molecular Axis ◽  
Small Deviations ◽  
Wave Absorption ◽  
Long Wave ◽  
Absolute Transition

A formula is derived for the absorption anisotropy K = (A∥ - A⊥) / (A∥ + 2A⊥ ) (where A∥ and A⊥ are the absorbances parallel and perpendicular to the stretching direction of the polymer film, respectively) as a function of the stretch ratio, Rs, of the film and the angle φ between the absorption transition moment direction and the long axis of a prolate molecule. Employing this relation, absolute transition moment directions (the angles φ) were determined experimentally for the following compounds: 1.8-diphenyloctatetraene (DPO), 1,6-diphenylhexatriene (DPH), 1.4-diphenylbutadiene (DPB), 4-dimethylamino-4'-nitrostilbene (DNS), 4-dimethylamino- 4'-chlorostilbene (DCIS) and p-terphenyl (TP). The directions were found to be along the long molecular axis in the long-wave absorption band. Small deviations of the angles obtained from (φ= 0°, which were of the order of several degrees, are due to the incomplete linearity of the molecules under investigation.

scholarly journals On the Determination of Transition-Moment Directions from Emission Anisotropy Measurements

1986 ◽  
Vol 41 (10) ◽  
pp. 1195-1199 ◽  
Author(s):  
A. Kawski ◽  
Z. Gryczyński
Keyword(s):  
Absorption Band ◽  
Polymer Film ◽  
Transition Moment ◽  
Emission Anisotropy ◽  
Wave Absorption ◽  
Long Wave ◽  
Linear Trans

Based on the theory of photoluminescence polarization, a description of the determination of transition-moment directions in luminescent molecules oriented in a stretched polymer film is given. This method is applied to the linear trans-diphenylpolyenes (C2h symmetry): 1,8-diphenyloctatetraene (DPO ), 1,6-diphenylhexatriene (DPH) and 1,4-diphenylbutadiene (DPB). The same transition moment polarized along the long axis o f DPO , DPH and DPB is responsible for absorption and fluorescence (β ≈ 0), when exciting in the long wave absorption band. The results are compared with relevant data obtained from dichroism measurements.

THE NATURE OF THE SPECIES RESPONSIBLE FOR THE LONG WAVE LENGTH ABSORPTION BAND IN ACIDIC SOLUTIONS OF OLEFINS

1960 ◽  
Vol 64 (3) ◽  
pp. 382-383 ◽  
Author(s):  
Harry P. Leptin ◽  
W. Keith Hall
Keyword(s):  
Absorption Band ◽  
Wave Length ◽  
Acidic Solutions ◽  
Long Wave

CNDO/2 (complete neglect of differential overlap)-method for third-row molecules

1973 ◽  
Vol 31 (3) ◽  
pp. 215-220 ◽  
Author(s):  
H. L. Hase ◽  
A. Schweig
Keyword(s):  
Complete Neglect ◽  
Overlap Method ◽  
Neglect Of Differential Overlap

Photochemistry of Aqueous Tetrathioantimonate(V)

1995 ◽  
Vol 50 (8) ◽  
pp. 1155-1157 ◽  
Author(s):  
H. Kunkely ◽  
A. Vogler
Keyword(s):  
Charge Transfer ◽  
Absorption Band ◽  
Electronic Spectrum ◽  
Redox Reaction ◽  
Elemental Sulfur ◽  
Metal Charge ◽  
Metal Charge Transfer

The electronic spectrum of [SbS4]3- in 10-3 M NaOH displays an absorption band at λmax = 285 nm which is assigned to a ligand-to-metal charge transfer (LMCT) transition. Upon LMCT excitation [SbS4]3- undergoes an intramolecular redox reaction with the formation of [SbS3]3- and elemental sulfur (φ = 0.11 at λirr = 333 nm).

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