Solvent effects on the two lowest-lying singlet excited states of 5-fluorouracil

Bistafa, Carlos; Canuto, Sylvio

doi:10.1007/s00214-012-1299-3

Cited by 29 publications

(30 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Compared to the electrostatic solvent methods PCM and ASEC, the inclusion of explicit solvent molecules decreases the transition energies. This trend was also seen in other systems . In both cases, the theoretical result disagrees with experiment, with the largest discrepancy being for CIS(D) that shifts in the wrong direction.…”

Section: Resultsmentioning

confidence: 52%

“…The resulting atomic charges were then fitted to the electrostatic potential computed in another calculation using the CHELPG scheme . This procedure allows the inclusion of polarization effects of the solvent over the solute in the S‐QM/MM scheme . The extended single point charge model (SPC/E) was used to represent the water molecules unless otherwise stated .…”

Section: Methodsmentioning

confidence: 99%

“…Among the several available correlation‐exchange functionals, B3LYP was chosen because of its well‐tested accuracy for electronic excitation calculations in molecules with nitro and methyl groups such as nitromethane . CIS(D) is a size consistent method that has a good balance between cost and accuracy . The ab initio ADC(2) method provides an accurate description of absorption spectra of polymers and other large systems .…”

Section: Methodsmentioning

confidence: 99%

“…The result is a single fictional configuration that is an average description of the solvent represented by point charges. Several applications of ASEC have shown that this single average configuration may be sufficient to obtain an average value of the electronic property with good accuracy . However, this simplification comes at the inevitable expense of the statistical distribution …”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂

2015

View full text Add to dashboard Cite

The first three valence transitions of the two nitromethane conformers (CH3NO2) are two dark n → π* transitions and a very intense π → π* transition. In this work, these transitions in gas-phase and solvated in water of both conformers were investigated theoretically. The polarizable continuum model (PCM), two conductor-like screening (COSMO) models, and the discrete sequential quantum mechanics/molecular mechanics (S-QM/MM) method were used to describe the solvation effect on the electronic spectra. Time dependent density functional theory (TDDFT), configuration interaction including all single substitutions and perturbed double excitations (CIS(D)), the symmetry-adapted-cluster CI (SAC-CI), the multistate complete active space second order perturbation theory (CASPT2), and the algebraic-diagrammatic construction (ADC(2)) electronic structure methods were used. Gas-phase CASPT2, SAC-CI, and ADC(2) results are in very good agreement with published experimental and theoretical spectra. Among the continuum models, PCM combined either with CASPT2, SAC-CI, or B3LYP provided good agreement with available experimental data. COSMO combined with ADC(2) described the overall trends of the transition energy shifts. The effect of increasing the number of explicit water molecules in the S-QM/MM approach was discussed and the formation of hydrogen bonds was clearly established. By including explicitly 24 water molecules corresponding to the complete first solvation shell in the S-QM/MM approach, the ADC(2) method gives more accurate results as compared to the TDDFT approach and with similar computational demands. The ADC(2) with S-QM/MM model is, therefore, the best compromise for accurate solvent calculations in a polar environment.

show abstract

Section: Resultsmentioning

confidence: 52%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂

2015

View full text Add to dashboard Cite

show abstract

“…The order was reversed for the intercalated samples, with a redshift of the π-π* transition to ca. 275 nm, due to the solvent effect of the surrounding water molecules in the interlayer space [37]. The blueshift in the lower intensity n-π* transition was difficult to observe experimentally.…”

Section: Resultsmentioning

confidence: 97%

5-Fluorouracil intercalated iron oxide@layered double hydroxide core-shell nano-composites with isotropic and anisotropic architectures for shape-selective drug delivery applications

Tuncelli

Zümreoǧlu‐Karan

2015

Materials Science and Engineering: C

View full text Add to dashboard Cite

Excited States Behavior of Nucleobases in Solution: Insights from Computational Studies

Improta

Barone

2014

Topics in Current Chemistry

View full text Add to dashboard Cite

We review the most significant results obtained in the study of isolated nucleobases in solution by quantum mechanical methods, trying to highlight also the most relevant open issues. We concisely discuss some methodological issues relevant to the study of molecular electronic excited molecular states in condensed phases, focussing on the methods most commonly applied to the study of nucleobases, i.e. continuum models as the Polarizable Continuum Model and explicit solvation models. We analyse how the solvent changes the relative energy of the lowest energy excited states in the Franck-Condon region, their minima and the Conical Intersections among the different states, interpreting the experimental optical spectra, both steady state and time-resolved. Several methods are available for accurately including solvent effects in the Franck-Condon region, and for most of the nucleobases the solvent shift on the different excited states can be considered assessed. The study of the excited state decay, both radiative and non-radiative, in solution still poses instead significant theoretical challenges.

show abstract

Solvent effects on the two lowest-lying singlet excited states of 5-fluorouracil

Cited by 29 publications

References 39 publications

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂

5-Fluorouracil intercalated iron oxide@layered double hydroxide core-shell nano-composites with isotropic and anisotropic architectures for shape-selective drug delivery applications

Excited States Behavior of Nucleobases in Solution: Insights from Computational Studies

Contact Info

Product

Resources

About

Solvent effects on the two lowest-lying singlet excited states of 5-fluorouracil

Cited by 29 publications

References 39 publications

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH3NO2

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH3NO2

5-Fluorouracil intercalated iron oxide@layered double hydroxide core-shell nano-composites with isotropic and anisotropic architectures for shape-selective drug delivery applications

Excited States Behavior of Nucleobases in Solution: Insights from Computational Studies

Contact Info

Product

Resources

About

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂

Water solvent effects using continuum and discrete models: The nitromethane molecule, CH₃NO₂