Optical properties of trans-stilbene using semiempirical and time-dependent density functional theory: A comparative study

Kwasniewski, Sergiusz; Deleuze, Michaël S.; François, J

doi:10.1002/1097-461x(2000)80:4/5<672::aid-qua16>3.0.co;2-8

Cited by 52 publications

(48 citation statements)

References 74 publications

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“…For stilbene, it appears 22,46,47 that the isolated molecule is planar at low temperature. However, gas phase measurements 48 indicate that the mean single bond rotation is about 30°.…”

Section: A Fitting the Spectramentioning

confidence: 99%

Screening and the quantitative π-model description of the optical spectra and polarizations of phenyl based oligomers

Castleton

Barford

2002

The Journal of Chemical Physics

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The long standing problem of the inability of many semiempirical models to correctly predict the polarization of the higher dipole allowed optical transitions of phenyl based -conjugated polymers and molecules is examined and related to the issue of internal and external screening ofelectron Coulomb interactions within the molecules. Following a review of previous theoretical and experimental work, electron only the Complete Neglect of Differential Overlap ͑CNDO͒ model is presented which, for the first time, is able to predict accurately the energies and symmetries of all the observed optical transitions of benzene, biphenyl and trans-stilbene, up to ϳ8 -10 eV. In so doing, it is demonstrated that the problem with previous calculations was the noninclusion of screening from outside the electron system itself. By fitting separately the spectra in hydrocarbon based condensed phases, in the gas phase and in solid rare gas matrices, and comparing the resulting model parameters, we show that, while the effects of screening from the environment are certainly noticeable, the most important spectral features-in particular the ordering of dipole allowed transitions-come from effective screening by the electrons. We find that both of these effects can be adequately accounted for within a electron only model by using a dielectric constant and appropriate parameter renormalization.

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“…For stilbene, it appears 22,46,47 that the isolated molecule is planar at low temperature. However, gas phase measurements 48 indicate that the mean single bond rotation is about 30°.…”

Section: A Fitting the Spectramentioning

confidence: 99%

Screening and the quantitative π-model description of the optical spectra and polarizations of phenyl based oligomers

Castleton

Barford

2002

The Journal of Chemical Physics

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“…Theoretical studies of the optical properties of TS have already pointed out that subtle variations of the -conjugation may have strong influence upon the outer valence levels [27]. Then, for each of the molecules considered, we have calculated the variation of the bond length distribution between the ground state (a singlet) and the first singlet excited state and between the ground state and the lowest triplet excited state.…”

Section: Resultsmentioning

confidence: 63%

“…5) considering the fully optimized 6-31G* geometries. Although the optical properties of TS have been extensively studied both at the theoretical [27,28] and experimental [9,29] levels, the TR and DSS molecules have been much less investigated. For the former, UV [30] and fluorescence [31] spectra became recently available.…”

Section: Resultsmentioning

confidence: 99%

Investigation of the excited states of resveratrol and related molecules

Nero

Melo

2003

Int J of Quantum Chemistry

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ABSTRACT:Resveratrol, a natural product derived from grapes, is a phytoalexin with antioxidative activity. In this work we present initial results of an ongoing study of the geometry of the ground state and of the first two (singlet and triplet) excited states of resveratrol and the structurally related compounds diethyl-stilbestrol-stilbene and trans-stilbene. The molecular geometries were optimized both at the semiempirical and ab initio (restricted Hartree-Fock/6-31G*) levels, and the corresponding absorption spectra were calculated using the intermediate neglect of differential overlap/ spectroscopically parameterized with interaction of configurations (INDO/S-CI) methodology.

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“…l calcd ϭ0.9804l obsd Ϫ11.5765; r 2 ϭ0.7099; nϭ43 (15) Those results showed that the linear relationship obtained by our g AA new -CNDO/S calculations was closer to the values of 1.0 and 0.0 (i.e., the slope and the intercept, respectively) than were those obtained by the NM-g CNDO/S calculations. …”

Section: Resultsmentioning

confidence: 84%

“…15,16) However, the absorption maxima wavelengths obtained by this TD-DFT calculations are calculated appreciably longer wavelengths for larger p-conjugated compounds, as compared to the observed maxima wavelengths beyond ca. 400 nm.…”

mentioning

confidence: 99%

Improved CNDO/S Calculation of Electronic Spectra of Organic Compounds. I. New CNDO/S Calculation by Using an Improved Method of One-Center Electron Repulsion Integral

Hata

Murakami²,

Shibuya

et al. 2006

CHEMICAL & PHARMACEUTICAL BULLETIN

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The semi-empirical CNDO/S, developed by Jaffé and coworkers, 1,2) and the ZINDO (so-called Zerner INDO/S) 3) methods are useful for the theoretical investigation of the electronic states and spectra of organic compounds. However, the usefulness of these methods for organic chemists is limited at present to the calculations of functional dyes, because the experimental absorption maxima wavelengths beyond approximately 400 nm are observed appreciably longer wavelengths, as compared to those of the ZINDO 3) and the conventional CNDO/S methods (referred to as NM-g CNDO/S) used in our previous paper.4) It is also known that the results of the absorption maxima wavelength calculated by the PPP method for p-electronic systems reflect substantial errors with the use of the NM-g CNDO/S and ZINDO methods. The reason for the large discrepancy between the calculated and observed values suggests that the calculated absorption maxima wavelengths in the organic compounds of larger p-conjugated systems cannot be reproduced within the allowed ranges as the experimental value, because the results of the orbital energies calculated by these theoretical methods result in a large difference between HOMO and LUMO orbital energies.Nishimoto 5) reported that the value of the ionization potential I m decreases, and that of the electron affinity A m increases with an increase in the number of mobile p-electrons in relatively large p-conjugated molecules. Moreover, they reported that this error produced by the conventional PPP method could be greatly improved by the reevaluation of the twocenter electronic repulsion integral (New-g), thus introducing the concept of chemical softness (referred to as New-g PPP).6-12) Furthermore, Nakayama and co-worker 13,14) also reported that the shortcomings of NM-g CNDO/S calculations are appreciably absent among the results of the modified CNDO/S and ZINDO (referred to as New-g CNDO/S and New-g INDO/S) calculations, which introduce a New-g using the concept of chemical softness for a number of polycyclic aromatic hydrocarbons. However, the New-g CNDO/S and New-g INDO/S methods cannot be applied to compounds other than p-conjugated aromatic hydrocarbons, because the New-g values have not yet been determined with respect to the p-conjugated compounds containing various hetero atoms, namely, there is a variable k-function for each bonds C-N, C-O, N-N, etc.In recent years, the time-dependent density functional theory (TD-DFT) has been considerably used for the analysis of the absorption spectra for the hydrocarbons.15,16) However, the absorption maxima wavelengths obtained by this TD-DFT calculations are calculated appreciably longer wavelengths for larger p-conjugated compounds, as compared to the observed maxima wavelengths beyond ca. 400 nm. And this method is too time-consuming to be calculated to the absorption maxima wavelengths for larger p-conjugated compounds.The goal of this investigation was to establish a general modified CNDO/S method of reproducing the observed absorption maxima wavelengths i...

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Optical properties of trans-stilbene using semiempirical and time-dependent density functional theory: A comparative study

Cited by 52 publications

References 74 publications

Screening and the quantitative π-model description of the optical spectra and polarizations of phenyl based oligomers

Screening and the quantitative π-model description of the optical spectra and polarizations of phenyl based oligomers

Investigation of the excited states of resveratrol and related molecules

Improved CNDO/S Calculation of Electronic Spectra of Organic Compounds. I. New CNDO/S Calculation by Using an Improved Method of One-Center Electron Repulsion Integral

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