Julien Preat

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The UV/visible spectra of a series of indigo derivatives have been evaluated by using ab initio methods. The combination of the Polarizable continuum model for estimating bulk solvent effects with the TD-B3LYP6-311 + G(2d,p)B3LYP6-311G(d,p) level of approximation, leads to an accurate description of the wavelength of maximum absorption of indigoids(More)
The structure and visible spectra of a large panel of thioindigo dyes and derivatives have been evaluated using a TD-PBE0/6-311+G(2d,p)//PBE0/6-311G(d,p) approach explicitly taking bulk solvent effects into account by means of the polarizable continuum model. The influence of the solvent characteristics, the trans-cis isomerization, and the chemical(More)
The UV absorption spectra of more than 80 substituted coumarins and chromones have been investigated with the PCM-TD-DFT theoretical scheme using three hybrid functionals (O3LYP, B3LYP, and PBE0) and taking into account methanol or ethanol solvation effects. For most of the studied derivatives, there are at least two allowed excited states presenting a(More)
We have investigated with computational chemistry techniques the visible spectra of substituted anthraquinones. A wide panel of theoretical methods has been used, with various basis sets and density functional theory (DFT) functionals, in order to assess a level of theory that would lead to converged excitation energies. It turns out that the hybrid(More)
We report the calculation of the UV spectra of more than 40 substituted coumarins and chromones in solution. In particular, two solvent models are compared, the multipolar expansion model (NCM) developed in Nancy and the PCM scheme developed in Pisa and Napoli. All calculations are carried out at the NCM-TDPBE0/6-311G(2d,2p)//NCM-B3LYP/6-311G(2d,2p) and at(More)
The UV/vis absorption spectra of 101 anthraquinones solvated in two protic solvents (methanol and ethanol) has been theoretically predicted using the time-dependent density functional theory (TD-DFT) for the excited state calculations and the polarizable continuum model (PCM) for evaluating bulk solvent effects. Two functionals (B3LYP and PBE0) have been(More)
The UV/visible spectra of a series of indirubin, isoindigo, and other indigo/thioindigo related dyes have been evaluated in various solvent environments by using the time-dependent density functional theory in conjunction with the polarizable continuum model. Even for molecules of the same family, significant differences in the excitation processes have(More)
We have computed the absorption spectra of a large series of anthraquinone dyes by using the time-dependent density functional theory (TD-DFT) for the excited-state calculations and the polarizable continuum model (PCM) for evaluating bulk solvent effects. On one hand, we compare the results obtained with the B3LYP and the PBE0 hybrid functionals, combined(More)
Using a state-of-the-art time-dependent density functional (TD-DFT) approach that includes the explicit consideration of bulk medium effects on both the ground-state geometry and the electronic spectrum, we have determined the lambda(max) of 86 naphthoquinones (NQ) dyes in various solvents for a total of 151 cases. In most cases, TD-DFT provides the correct(More)
Tuning sensing abilities! The affinity of three different [15]crown-5 ether functionalized polythiophenes for alkali ions has been explored (see figure). Ab initio and DFT quantum mechanical calculations show that the binding energy between neutral conducting polymers and metallic ions, which interact attractively, decreases as the size of the ion(More)