DFT and TD-DFT calculation of new thienopyrazine-based small molecules for organic solar cells

Bourass, Mohamed; Benjelloun, Adil Touimi; Benzakour, M.; Mcharfi, Mohammed; Hamidi, M.; Bouzzine, Si Mohamed; Bouachrine, Mohammed

doi:10.1186/s13065-016-0216-6

Cited by 113 publications

(64 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, in order to identify the functional most suited to simulate all spectroscopies of interest, preliminary benchmarks based on both the OPA and ECD spectra were performed. A subset of functionals known to provide reliable results on similar system was chosen, namely CAM-B3LYP (Yanai et al, 2004 ), LC-ωPBE (Vydrov and Scuseria, 2006 ), M06-2X (Valero et al, 2008 ), MN15 (Haoyu et al, 2016 ), PBE0 (Adamo and Barone, 1999 ), and ωB97X-D (Chai and Head-Gordon, 2008 ). For CAM-B3LYP and PBE0, the D3 formulation of the empirical dispersion correction proposed by Grimme et al ( 2010 ), in conjunction with the Becke-Johnson (BJ) damping (Grimme et al, 2011 ) were used.…”

Section: Resultsmentioning

confidence: 99%

Theoretical Investigation of the Circularly Polarized Luminescence of a Chiral Boron Dipyrromethene (BODIPY) Dye

2020

View full text Add to dashboard Cite

Over the last decade, molecules capable of emitting circularly polarized light have attracted growing attention for potential technological and biological applications. The efficiency of such devices depend on multiple parameters, in particular the magnitude and wavelength of the peak of emitted light, and also on the dissymmetry factor for chiral applications. In light of these considerations, molecular systems with tunable optical properties, preferably in the visible spectral region, are particularly appealing. This is the case of boron dipyrromethene (BODIPY) dyes, which exhibit large molecular absorption coefficients, have high fluorescence yields, are very stable, both thermally and photochemically, and can be easily functionalized. The latter property has been extensively exploited in the literature to produce chromophores with a wide range of optical properties. Nevertheless, only a few chiral BODIPYs have been synthetized and investigated so far. Using a recently reported axially chiral BODIPY derivative where an axially chiral BINOL unit has been attached to the chromophore unit, we present a comprehensive computational protocol to predict and interpret the one-photon absorption and emission spectra, together with their chiroptical counterparts. From the physico-chemical properties of this molecule, it will be possible to understand the origin of the circularly polarized luminescence better, thus helping to fine-tune the properties of interest. The sensitivity of such processes require accurate results, which can be achieved through a proper account of the vibrational structure in optical spectra. Methodologies to compute vibrationally-resolved electronic spectra can now be applied on relatively large chromophores, such as BODIPYs, but require more extensive computational protocols. For this reason, particular attention is paid in the description of the different steps of the protocol, and the potential pitfalls. Finally, we show how, by means of appropriate tools and approaches, data from intermediate steps of the simulation of the final spectra can be used to obtain further insights into the properties of the molecular system under investigation and the origin of the visible bands.

show abstract

Section: Resultsmentioning

confidence: 99%

Theoretical Investigation of the Circularly Polarized Luminescence of a Chiral Boron Dipyrromethene (BODIPY) Dye

2020

View full text Add to dashboard Cite

show abstract

“…To this aim, we extracted 30 snapshots sequentially from the trajectory, from each snapshot we cut a sphere of 30 Å centered around the solute and we assembled them into a collective configuration and we assigned to each environmental atom 1/30 of the actual atomic charge. The first 11 electronic states and the complete matrix of the corresponding dipole moments were computed for the 4 reference configurations exploiting the ONIOM/EE model with the QM part described at the TD-DFT/CAM-B3LYP (Yanai et al, 2004 ) level in conjunction with the jul-cc-pVDZ (Dunning, 1989 ; Papajak et al, 2011 ) basis set. For each electronic state, the corresponding atomic charges were also computed at the same computational level using the CM5 recipe.…”

Section: Methodsmentioning

confidence: 99%

CPL Spectra of Camphor Derivatives in Solution by an Integrated QM/MD Approach

2020

View full text Add to dashboard Cite

We extend a recently proposed computational strategy for the simulation of absorption spectra of semi-rigid molecular systems in condensed phases to the emission spectra of flexible chromophores. As a case study, we have chosen the CPL spectrum of camphor in methanol solution, which shows a well-defined bisignate shape. The first step of our approach is the quantum mechanical computation of reference spectra including vibrational averaging effects and taking bulk solvent effects into account by means of the polarizable continuum model. In the present case, the large amplitude inversion mode is explicitly treated by a numerical approach, whereas the other small-amplitude vibrational modes are taken into account within the harmonic approximation. Next, the snapshots of classical molecular dynamics computations are clusterized and one representative configuration from each cluster is used to compute a reference spectrum. In the present case, different clusters correspond to the two stable conformers of camphor in the S1 excited electronic state and, for each of them, to different numbers of strong solute-solvent hydrogen bonds. Finally, local fluctuation effects within each cluster are taken into account by means of the perturbed matrix model. The overall procedure leads to good agreement with experiment for absorption and emission spectra together with their chiral counterparts, thus allowing to analyze the role of different effects (stereo-electronic, vibrational, environmental) in tuning the overall experimental spectra.

show abstract

“…For this, we employed six popular exchange-correlation functionals on the molecule CTRZ which has been well-characterized experimentally in previous works (An et al, 2011 ; Duan et al, 2018 ) as well as in this work. We used two range-separated hybrid functionals, CAM-B3LYP (Yanai et al, 2004 ) and ωB97XD (Chai and Head-Gordon, 2008 ), three hybrid meta-GGA functionals, M06-2X (56% exact exchange), M06-HF (100 % exact exchange) (Zhao and Truhlar, 2008 ) and PW6B95D3(28% exact exchange) (Zhao and Truhlar, 2005 ) and a meta-GGA functional, PBE0(25% exact exchange) (Adamo and Barone, 1999 ). Table 1 compares the calculated S 1 and T 1 emission energies, in the relaxed excited state geometry, obtained for CTRZ with these 6 functionals with the experimentally measured value (see next section).…”

Section: Td-dft-analysismentioning

confidence: 99%

High Triplet Energy Host Materials for Blue TADF OLEDs—A Tool Box Approach

et al. 2020

View full text Add to dashboard Cite

The synthesis of stable blue TADF emitters and the corresponding matrix materials is one of the biggest challenges in the development of novel OLED materials. We present six bipolar host materials based on triazine as an acceptor and two types of donors, namely, carbazole, and acridine. Using a tool box approach, the chemical structure of the materials is changed in a systematic way. Both the carbazole and acridine donor are connected to the triazine acceptor via a para-or a meta-linked phenyl ring or are linked directly to each other. The photophysics of the materials has been investigated in detail by absorption-, fluorescence-, and phosphorescence spectroscopy in solution. In addition, a number of DFT calculations have been made which result in a deeper understanding of the photophysics. The presence of a phenyl bridge between donor and acceptor cores leads to a considerable decrease of the triplet energy due to extension of the overlap electron and hole orbitals over the triazine-phenyl core of the molecule. This decrease is more pronounced for the para-phenylene than for the meta-phenylene linker. Only direct connection of the donor group to the triazine core provides a high energy of the triplet state of 2.97 eV for the carbazole derivative CTRZ and 3.07 eV for the acridine ATRZ. This is a major requirement for the use of the materials as a host for blue TADF emitters.

show abstract

DFT and TD-DFT calculation of new thienopyrazine-based small molecules for organic solar cells

Cited by 113 publications

References 50 publications

Theoretical Investigation of the Circularly Polarized Luminescence of a Chiral Boron Dipyrromethene (BODIPY) Dye

Theoretical Investigation of the Circularly Polarized Luminescence of a Chiral Boron Dipyrromethene (BODIPY) Dye

CPL Spectra of Camphor Derivatives in Solution by an Integrated QM/MD Approach

High Triplet Energy Host Materials for Blue TADF OLEDs—A Tool Box Approach

Contact Info

Product

Resources

About