The Electric Dipole Moments of Methine Dyes – Comparison of Experimental Results with Theoretical Predictions

Abstract Absorption and emission spectra of methine dyes in polar and nonpolar solvents were measured. From the Stokes shift as a function of solvent polarity the dipole moments of excited singlet states have been estimated and compared with the quantum chemical predictions. Also the π-electronic charge distribution in the ground and first excited singlet electronic states and bond orders of the dyes were calculated. All investigated methines showed an increase in dipole moment upon excitation to the first excited emitting state.

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ChemInform Abstract: Dipole Moments of Indoles in Their Ground and the First Excited Singlet States.

Chemischer Informationsdienst ◽

10.1002/chin.198622038 ◽

1986 ◽

Vol 17 (22) ◽

Author(s):

C. PARKANYI ◽

S. R. ORUGANTI ◽

A. O. ABDELHAMID ◽

L. VON SZENTPALY ◽

B. NGOM ◽

...

Keyword(s):

Dipole Moments ◽

Excited Singlet ◽

Singlet States ◽

Excited Singlet States

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On the dipole moments of excited singlet states of carbon monoxide

Canadian Journal of Physics ◽

10.1139/p76-030 ◽

1976 ◽

Vol 54 (3) ◽

pp. 258-261 ◽

Cited By ~ 11

Author(s):

Nina J. Fisher ◽

F. W. Dalby

Keyword(s):

Carbon Monoxide ◽

Dipole Moment ◽

Dipole Moments ◽

Excited Singlet ◽

Electric Dipole Moments ◽

Upper Limit ◽

Singlet States ◽

Stark Effects ◽

Excited Singlet States ◽

Π State

The electric dipole moments of the B1Σ+, C1Σ+, and A1Π states of the CO molecule have been determined by observing Stark effects on the Ångstrom and Herzberg bands. We find the excited B and C states to have dipole moments of (1.60 ± 0.15) and (4.52 ± 0.35) D respectively. The upper limit for the dipole moment of the A1Π state is (0.15 ± 0.05) D.

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Structures, dipole moments and excited state lifetime of isolated 4-cyanoindole in its ground and lowest electronically excited singlet states

Physical Chemistry Chemical Physics ◽

10.1039/c9cp01618j ◽

2019 ◽

Vol 21 (27) ◽

pp. 14766-14774 ◽

Cited By ~ 3

Author(s):

Marie-Luise Hebestreit ◽

Michael Schneider ◽

Hilda Lartian ◽

Vivienne Betz ◽

Michael Heinrich ◽

...

Keyword(s):

Excited State ◽

Dipole Moments ◽

Excited State Lifetime ◽

Excited Singlet ◽

Singlet States ◽

Electronically Excited ◽

Excited Singlet States

The rotationally resolved electronic Stark spectrum of 4-cyanoindole and some N-D and C-D deuterated isotopologues has been measured and analyzed.

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ChemInform Abstract: Experimental and Theoretical Dipole Moments of Purines in Their Ground and Lowest Excited Singlet States.

ChemInform ◽

10.1002/chin.198720040 ◽

1987 ◽

Vol 18 (20) ◽

Author(s):

J.-J. AARON ◽

M. D. GAYE ◽

C. PARKANYI ◽

N. S. CHOU ◽

L. VON SZENTPALY

Keyword(s):

Dipole Moments ◽

Excited Singlet ◽

Singlet States ◽

Excited Singlet States

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Carbon dioxide as a quencher of fluorescence

Australian Journal of Chemistry ◽

10.1071/ch9732715 ◽

1973 ◽

Vol 26 (12) ◽

pp. 2715 ◽

Cited By ~ 2

Author(s):

RJ McDonald ◽

BK Selinger

Keyword(s):

Carbon Dioxide ◽

Solvent Polarity ◽

Excited Singlet ◽

Singlet States ◽

Exciplex Emission ◽

Excited Singlet States

Carbon dioxide is found to form a reversible quench complex with the excited singlet states of certain amines. No separate exciplex emission could be observed and the complexation was not dependent on solvent polarity. Irradiation leads to photochemical products.

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Experimental and theoretical dipole moments of purines in their ground and lowest excited singlet states

Journal of Molecular Structure ◽

10.1016/0022-2860(87)85046-9 ◽

1987 ◽

Vol 156 (1-2) ◽

pp. 119-135 ◽

Cited By ~ 45

Author(s):

Jean-Jacques Aaron ◽

Mame Diabou Gaye ◽

Cyril Párkányi ◽

Nam Sook Cho ◽

László Von Szentpály

Keyword(s):

Dipole Moments ◽

Excited Singlet ◽

Singlet States ◽

Excited Singlet States

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Estimating the Ground and Excited State Dipole Moments of Levofloxacin and Norfloxacin Drugs Using Solvatochromic Effects and Computational Work

Journal of Spectroscopy ◽

10.1155/2021/7214182 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Kinfe Woldegiorges ◽

Abebe Belay ◽

Alemu Kebede ◽

Tamirat Abebe

Keyword(s):

Excited State ◽

Ground State ◽

Dipole Moments ◽

Bacterial Species ◽

Emission Spectra ◽

Solvent Polarity ◽

Electron Charge Density ◽

Nonpolar Solvents ◽

Computational Work ◽

Excited State Dipole Moments

Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectrum used to treat various infections caused by many bacterial species. The drugs contain functional groups which control the type and degree of interaction with different solvents. In this research, the ground and excited state dipole moments of LVF and NRF drugs were estimated using solvatochromic effects and computational work. The dipole moments were estimated from absorption and emission spectra in polar and nonpolar solvents using Bakhshiev’s, Kawski–Chamma–Viallet, Lippert–Mataga, and Reichardt models. The results indicated the emission spectra are more strongly affected by solvent polarity than the absorption spectra. The calculated excited state dipole moment is larger than that of the ground state, indicating that the probe compounds are significantly more polarized in the excited state than in the ground state. From computational work, the HOMO-LUMO energy band gap, the dipole moments, electron charge density distribution, and oscillator strength were determined using the semiempirical MP6 method, DFT-B3LYP-6-31G, and DFT-B3LYP-3-21G employing Gaussian 09 software. In general, larger dipole moments were obtained by computation rather than from experiments due to the absence of solvent effects.

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