Studies on Photophysical Properties of Mono-carbonyl Curcumin Analogues: Experimental and Theoretical approach

The solvatochromic fluorescence behaviour of mono-carbonyl curcumin analogues has been studied in ten different solvents ranging from non-polar to polar. The solvent effect on the spectral properties of analogues has been discussed. The ground state dipole moments were estimated experimentally by Bilot-Kawski equation which is a function of Stokes shift with the solvent polarity parameters and Guggenheim method and theoretically by TD-DFT studies. The excited state dipole moment was determined using Bilot-Kawski equations. The excited state dipole moments for the two molecules were found to be higher than their corresponding ground state dipole moments. Theoretically Frontier molecular orbital (HOMO/ LUMO) energies were determined by Gaussian 09 W software using TD-DFT.

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A semi-empirical estimation of ground and excited state dipole moments of zinc phthalocyanine from solvatochromic shift data

International Journal of Advanced Chemistry ◽

10.14419/ijac.v6i2.11019 ◽

2018 ◽

Vol 6 (2) ◽

pp. 190

Author(s):

Abimbola Ogunsipe

Keyword(s):

Excited State ◽

Ground State ◽

Dipole Moments ◽

Solvent Polarity ◽

Zinc Phthalocyanine ◽

Empirical Estimation ◽

Solvatochromic Shift ◽

Excited State Dipole Moments ◽

Semi Empirical ◽

Ground State Dipole Moments

A semi-empirical determination of ground and excited state dipole moments of zinc phthalocyanine (ZnPc) from solvatochromic shifts is hereby presented. The ratio of the excited- and ground-state dipole moments of ZnPc ( ) was estimated by a combination of the Bakshiev and the Kawski-Chamma-Viallet’s equations, while the difference in the excited- and ground-state dipole moments (Dm) was estimated usingthe molecular-microscopic solvent polarity parameters ( ), alongside the Stokes’ shifts (Dῡ) in the various solvents. The dipole moment of ZnPc is significantly higher in the excited singlet state (me = 3.12 D) than in the ground state (mg = 1.50 D). Obviously charge separation is greater in the excited state of ZnPc than in its ground state.

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Dipole moments and quenching of fluorescence of a new coumarin dye

Canadian Journal of Physics ◽

10.1139/cjp-2019-0517 ◽

2020 ◽

Vol 98 (8) ◽

pp. 761-769

Author(s):

Omnath Patil ◽

P.K. Ingalagondi ◽

Shivaraj Gounhalli ◽

S.M. Hanagodimath

Keyword(s):

Activation Energy ◽

Excited State ◽

Ground State ◽

Density Functional ◽

Dipole Moments ◽

Fluorescence Emission ◽

Solvent Polarity ◽

Chemical Hardness ◽

Fluorescence Emission Spectra ◽

Coumarin Dye

The absorption and fluorescence emission spectra of a newly synthesized laser grade coumarin dye, 1-((4-methoxyphenoxy) methyl)-3H-benzo[f]chromen-3-one (4-MPMBC), have been recorded in various solvents having different polarities. The spectrum peak was found to shift toward a higher wavelength with an increase in the solvent polarity. The dipole moments of the ground state (μg) and excited state (μe) were estimated using the Lippert, Bakshiev, and Kawski–Chamma–Viallet equations. The μe values were found to be greater than the μg values in all solvents, indicating that the dye is more polar in the excited state than in the ground state. The absorption maximum and emission maximum energies, ground- and excited-state dipole moments, and HOMO–LUMO energy gaps were estimated using Gaussian 16W. These have been compared with the experimental results. The estimated chemical hardness of the dye molecule indicates the soft nature in all of the solvents. The reactive centers such as nucleophilic and electrophilic sites were identified along with contour action using electrostatic potential three-dimensional map density functional theory analysis. The fluorescence quenching has been studied in solvents of varying polarities using aniline as a quencher. The quenching process was found to follow the Stern–Volmer equation and was studied by considering the role of diffusion. In all solvents, the probability of quenching per encounter (p) was found to be less than unity. The activation energy for diffusion and activation energy for quenching were estimated using the values of p.

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Effect of solvent polarity on the photophysical properties of chalcone derivatives

RSC Advances ◽

10.1039/c7ra01705g ◽

2017 ◽

Vol 7 (39) ◽

pp. 24204-24214 ◽

Cited By ~ 13

Author(s):

Rekha Kumari ◽

Anitha Varghese ◽

Louis George ◽

Sudhakar Y. N.

Keyword(s):

Excited State ◽

Organic Solvents ◽

Ground State ◽

Photophysical Properties ◽

Solvent Polarity ◽

Chalcone Derivatives ◽

Effect Of Solvent

The photophysical properties were studied for FNPO, AFPO and FHPO in different organic solvents. The excited state of the molecules were found to be more polar than the ground state.

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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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Solvatochromic Study of Supramolecular Amphiphile Based on Calix[4]arene Connected to a Fluorescent Benzofurazan Moiety at Lower Rim: Evaluation of Ground and Excited State Dipole Moments-=SUP=-*-=/SUP=-

Журнал технической физики ◽

10.21883/os.2020.12.50322.1028-20 ◽

2020 ◽

Vol 128 (12) ◽

pp. 1864

Author(s):

S. Joshi

Keyword(s):

Dipole Moment ◽

Excited State ◽

Ground State ◽

Fluorescence Spectra ◽

Dipole Moments ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Fluorescence Emission ◽

Wide Range ◽

Excited State Dipole Moment

Photophysical properties of a supramolecular amphiphile of calix[4]arene having benzofurazan moiety at the lower rim, L has been studied. Electronic absorption and fluorescence spectra of L have been recorded in wide range of solvents of different polarities and data were used to study solvatochromic properties. The ground state and the excited state dipole moment of L were estimated from the Bakhshiev's and Bilot-Kawaski's equations. High value of dipole moment is observed for excited state as compared to ground state value and this is attributed to more polar excited state of molecule. Also, fluorescence emission peak undergoes a bathochromic shift with increase in the polarity of the solvent, confirming π-> π* transition. Scanning electron microscopy reveals that the aggregation of L is increased on going from the polar to non polar solvents. Keywords: solvatochromism, benzofurazan, dipole moment, quantum yield, absorption, fluoresence.

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Study of Solvent Effect in 2, 5-DPAPMC Dye Using Different Solvent Polarity Parameters and Estimation of Dipole Moments

Mapana Journal of Sciences ◽

10.12723/mjs.28.7 ◽

2017 ◽

Vol 13 (1) ◽

pp. 101-117

Author(s):

Thipperudrappa J

Keyword(s):

Dipole Moment ◽

Excited State ◽

Linear Regression ◽

Ground State ◽

Dipole Moments ◽

Solvent Polarity ◽

Ground State Dipole Moment ◽

Regression Approach ◽

Polarity Parameter ◽

Excited State Dipole Moment

The solvent effect on absorption and fluorescence spectra of a ketocyanine dye 2,5-di[(E)-1-(4- dipropylaminophenyl) methylidine]-1-cyclopentanone (2,5-DPAPMC) is analysed using Lippert-Mataga bulk polarity function, Reichardt’s microscopic solvent polarity parameter and Kamlet’s multipl e linear regression approach. The spectral properties better follows Reichardt’s microscopic solvent polarity parameter than Lippert-Mataga bulk polarity parameter. This indicates the presence of both general solute – solvent interactions and specific interactions. Kamlet’s multiple linear regression approach indicates the major role of polarizability/dipolarity solvent influence than HBD and HBA. The spectral data in different solvents is used to estimate excited state dipole moment using theoretically determined ground state dipole moment. The excited state dipole moment of dye is found to be larger than its corresponding ground state dipole moment and, ground and excited state dipole moments are not parallel, but subtends an angle of 29 o .

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