scholarly journals Donor-Acceptor Substituted Benzo-, Naphtho- and Phenanthro-Fused Norbornadienes

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 322 ◽  
Author(s):  
Mads Mansø ◽  
Lorette Fernandez ◽  
Zhihang Wang ◽  
Kasper Moth-Poulsen ◽  
Mogens Brøndsted Nielsen
Keyword(s):  
Visible Region ◽  
Energy Difference ◽  
Sonogashira Coupling ◽  
Solar Thermal Energy ◽  
Absorption Properties ◽  
Structural Modifications ◽  
Acceptor Group ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Selection Of

The photochromic norbornadiene/quadricyclane (NBD/QC) couple has found interest as a molecular solar thermal energy (MOST) system for storage of solar energy. To increase the energy difference between the two isomers, we present here the synthesis of a selection of benzo-fused NBD derivatives that contain an aromatic unit, benzene, naphthalene or phenanthrene, fused to one of the NBD double bonds, while the carbon atoms of the other double bond are functionalized with donor and acceptor groups. The synthesis protocols involve functionalization of benzo-fused NBDs with bromo/chloro substituents followed by a subjection of these intermediates to a cyanation reaction (introducing a cyano acceptor group) followed by a Sonogashira coupling (introducing an arylethynyl donor group, -C≡CC6H4NMe2 or -C≡CC6H4OMe). While the derivatives have good absorption properties in the visible region (redshifted relative to parent system) in the context of MOST applications, they lack the ability to undergo NBD-to-QC photoisomerization, even in the presence of a photosensitizer. It seems that loss of aromaticity of the fused aromatics is too significant to allow photoisomerization to occur. The concept of destroying aromaticity of a neighboring moiety as a way to enhance the energy density of the NBD/QC couple thus needs further structural modifications, in the quest for optimum MOST systems.

Modulation of band gap and p- versus n-semiconductor character of ADA dyes by core and acceptor group variation

2016 ◽  
Vol 3 (5) ◽  
pp. 545-555 ◽  
Author(s):  
Agnieszka Nowak-Król ◽  
Reinhard Wagener ◽  
Felix Kraus ◽  
Amaresh Mishra ◽  
Peter Bäuerle ◽  
...  
Keyword(s):  
Band Gap ◽  
Building Blocks ◽  
Acceptor Group ◽  
Donor And Acceptor ◽  
Type Semiconductor ◽  
Group Variation ◽  
Donor Acceptor ◽  
Semiconductor Character

By variation of donor and acceptor building blocks in acceptor–donor–acceptor dyes a transition from p- to n-type semiconductor has been achieved.

Improving the electrical and optical properties of C50 fullerene using the Donor-Acceptor groups

2021 ◽  
Author(s):  
Ali Ayoubikaskooli ◽  
Abdol Mohammad Ghaedi ◽  
Hamid Reza Shamlouei ◽  
Yadollah Saghapour
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Infrared Region ◽  
Absorption Bands ◽  
Visible Absorption ◽  
Acceptor Group ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Linear Optical Properties ◽  
Uv Visible

Abstract In this research, the C50 fullerene was employed as the source of the π electrons and the electron donor-acceptor groups were used to enhance its optical properties. Considerable enhancement in its electronic and optical property of as the result of donor and acceptor group presence was observed. For instance, in UV-Visible absorption spectrum, the number of absorption lines significantly increase which may be the relaxation of the electronic transition selection rules. Considerably, the substituted forms of C50, has numbers of absorption bands in near infrared region. The BH2–C50-NCH3Li and NO–C50-NCH3Li molecules have superior improvement in optical properties. Finally, the donor and acceptor groups influence on non-linear optical properties (NLO) of C50 were explored and the considerable improvement in NLO properties of C50 was observed which the NLO improvements for BH2-C50-NCH3Li and NO-C50-CH2Li cases is higher than others.

Two Excited State Structures of Donor-Acceptor Substituted "Proton Sponge"

2005 ◽  
Vol 277-279 ◽  
pp. 1060-0 ◽  
Author(s):  
A. Szemik Hojniak ◽  
I. Deperasińska ◽  
W.J. Buma ◽  
G. Balkowski ◽  
A.F. Pozharsky ◽  
...  
Keyword(s):  
Absorption Spectrum ◽  
Excited State ◽  
Ground State ◽  
Experimental Spectrum ◽  
Proton Sponge ◽  
Strong Electron ◽  
Acceptor Group ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Ab Initio Hf

Photoexcitation of “proton sponge” 1,8-bis (dimethylamino) naphthalene (DMAN) leads to charge transfer (CT) emission. This work demonstrates that substitution of DMAN with a strong electron acceptor group (CN) results in CN-DMAN and leads to a stronger orbital decoupling between the Donor and Acceptor groups and to a more effective CT process (λF = 630 nm). The theoretical absorption spectrum calculated for CN-DMAN using the ZINDO method on its ground state ab initio [HF/6-31G(d)] optimized geometry reproduces a better experimental spectrum than that calculated using the RCIS method. It also shows that AM1 excited state (1La) optimization reveals two quasi-degenerated states with anti-quinoidal (A) and quinoidal (B) structures and the CT nature. Both structures may contribute more or less equally to the fluorescence of CN-DMAN in a solution.

scholarly journals Thermochromic aggregation-induced dual phosphorescence via temperature-dependent sp3-linked donor-acceptor electronic coupling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Tao Wang ◽  
Zhubin Hu ◽  
Xiancheng Nie ◽  
Linkun Huang ◽  
Miao Hui ◽  
...  
Keyword(s):  
Excited State ◽  
Room Temperature ◽  
Electronic Coupling ◽  
Temperature Dependent ◽  
Molecular Systems ◽  
Donor And Acceptor ◽  
Theoretical Investigations ◽  
Donor Acceptor ◽  
And Control ◽  
Two Temperature

AbstractAggregation-induced emission (AIE) has proven to be a viable strategy to achieve highly efficient room temperature phosphorescence (RTP) in bulk by restricting molecular motions. Here, we show that by utilizing triphenylamine (TPA) as an electronic donor that connects to an acceptor via an sp3 linker, six TPA-based AIE-active RTP luminophores were obtained. Distinct dual phosphorescence bands emitting from largely localized donor and acceptor triplet emitting states could be recorded at lowered temperatures; at room temperature, only a merged RTP band is present. Theoretical investigations reveal that the two temperature-dependent phosphorescence bands both originate from local/global minima from the lowest triplet excited state (T1). The reported molecular construct serves as an intermediary case between a fully conjugated donor-acceptor system and a donor/acceptor binary mix, which may provide important clues on the design and control of high-freedom molecular systems with complex excited-state dynamics.

scholarly journals Supramolecular Systems Containing B–N Frustrated Lewis Pairs of Tris(pentafluorophenyl)borane and Triphenylamine Derivatives

2021 ◽  
Vol 03 (02) ◽  
pp. 174-183
Author(s):  
P. Chidchob ◽  
S. A. H. Jansen ◽  
S. C. J. Meskers ◽  
E. Weyandt ◽  
N. P. van Leest ◽  
...  
Keyword(s):  
Materials Science ◽  
Supramolecular Polymers ◽  
Frustrated Lewis Pairs ◽  
Paramagnetic Resonance ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Noncovalent Polymers ◽  
Electron Paramagnetic ◽  
Supramolecular Polymerization ◽  
Lewis Pairs

The introduction of a chemical additive to supramolecular polymers holds high potential in the development of new structures and functions. In this regard, various donor- and acceptor-based molecules have been applied in the design of these noncovalent polymers. However, the incorporation of boron–nitrogen frustrated Lewis pairs in such architectures is still rare despite their many intriguing properties in catalysis and materials science. The limited choices of suitable boron derivatives represent one of the main limitations for the advancement in this direction. Here, we examine the use of the commercially available tris(pentafluorophenyl)borane with various triphenylamine derivatives to create supramolecular B–N charge transfer systems. Our results highlight the importance of a proper balance between the donor/acceptor strength and the driving force for supramolecular polymerization to achieve stable, long-range ordered B–N systems. Detailed analyses using electron paramagnetic resonance and optical spectroscopy suggest that tris(pentafluorophenyl)borane displays complex behavior with the amide-based triphenylamine supramolecular polymers and may interact in dimers or larger chiral aggregates, depending on the specific structure of the triphenylamines.

scholarly journals Pyran-Squaraine as Photosensitizers for Dye-Sensitized Solar Cells: DFT/TDDFT Study of the Electronic Structures and Absorption Properties

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Reda M. El-Shishtawy ◽  
Shaaban A. Elroby ◽  
Abdullah M. Asiri ◽  
Rifaat H. Hilal
Keyword(s):  
Solar Cells ◽  
Dye Sensitized Solar Cells ◽  
Nbo Analysis ◽  
Basis Set ◽  
Absorption Properties ◽  
Charge Delocalization ◽  
Squaraine Dyes ◽  
Dye Sensitized ◽  
Donor Acceptor ◽  
Sensitized Solar Cells

In an effort to provide, assess, and evaluate a theoretical approach which enables designing efficient donor-acceptor dye systems, the electronic structure and optical properties of pyran-squaraine as donor-acceptor dyes used in dye-sensitized solar cells were investigated. Ground state properties have been computed at the B3LYP/6-31+G**level of theory. The long-range corrected density functionals CAM-B3LYP, PBEPBE, PBE1PBE (PBE0), and TPSSH with 6-311++G**were employed to examine absorption properties of the studied dyes. In an extensive comparison between experimental results and ab initio benchmark calculations, the TPSSH functional with 6-311++G**basis set was found to be the most appropriate in describing the electronic properties for the studied pyran and squaraine dyes. Natural transition orbitals (NTO), frontier molecular orbitals (FMO), LUMO, HOMO, and energy gaps, of these dyes, have been analyzed to show their effect on the process of electron injection and dye regeneration. Interaction between HOMO and LUMO of pyran and squaraine dyes was investigated to understand the recombination process and charge-transfer process involving these dyes. Additionally, we performed natural bond orbital (NBO) analysis to investigate the role of charge delocalization and hyperconjugative interactions in the stability of the molecule.

Controlling charge transfer in fullerene/phthalocyanine electron donor-acceptor conjugates/hybrids

2009 ◽  
Vol 13 (10) ◽  
pp. 1034-1039 ◽  
Author(s):  
Wolfgang Seitz ◽  
Axel Kahnt ◽  
Dirk M. Guldi ◽  
Tomas Torres
Keyword(s):  
Three Dimensional ◽  
Reorganization Energy ◽  
Model Systems ◽  
Transfer Reactions ◽  
Dimensional Electron ◽  
Specific Composition ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Light Harvesting Antenna ◽  
Energetic Charge

Fullerenes and phthalocyanines are ideally suited for devising integrated, multi-component model systems to transmit and process solar energy. Implementation of C 60 as a three-dimensional electron acceptor bears great promises on account of its small reorganization energy in electron transfer reactions and has exerted a noteworthy impact on the improvement of light-induced charge separation. This mini-review describes how the specific composition of phthalocyanines chromophores associated with C 60 – yielding artificial light-harvesting antenna and reaction center mimics – have been elegantly utilized to tune the electronic couplings between donor and acceptor sites. Specifically, the effects that these parameters have on the rate, yield and lifetime of the energetic charge-separated states are considered.

scholarly journals Donor Acceptor Copolymers from Cyclopentannulation Polymerizations with Dicyclopenta[cd,jk]pyrene and Dicyclopenta[cd,lm]perylene Acceptors

2020 ◽  
Author(s):  
Ain Uddin ◽  
Kyle Plunkett
Keyword(s):  
Thin Film ◽  
Cyclic Voltammetry ◽  
Light Absorption ◽  
Visible Region ◽  
Optoelectronic Properties ◽  
Band Gaps ◽  
Molecular Weights ◽  
Palladium Catalyzed ◽  
Donor Acceptor ◽  
Film Absorption

A series of donor-acceptor copolymers with dicyclopenta[cd,jk]pyrene and dicyclopenta[cd,lm]perylene acceptor units was prepared via palladium catalyzed cyclopenta-annulation reactions. The acceptor units were paired with diethynyl containing donor groups based on benzo[1,2-b:4,5-b']dithiophene, thieno[3,2-b]thiophene, and 4-octyl-4H-dithieno[3,2-b:2',3'-d]pyrrole to create six polymer variants. The cyclopentannulation polymerization resulted in copolymers with molecular weights (Mn) of 6-14 kDa and broad light absorption in the visible region with band gaps of 1.38-1.85 eV. The synthetic methodology, as well as optoelectronic properties, including thin-film absorption and cyclic voltammetry, of the donor-acceptor copolymers are presented.<br> <br><br>

scholarly journals Spectral fine tuning of cyanine dyes: electron donor–acceptor substituted analogues of thiazole orange

2015 ◽  
Vol 14 (9) ◽  
pp. 1703-1712 ◽  
Author(s):  
Elizabeth E. Rastede ◽  
Matteus Tanha ◽  
David Yaron ◽  
Simon C. Watkins ◽  
Alan S. Waggoner ◽  
...  
Keyword(s):  
Electron Donor ◽  
Emission Spectra ◽  
Fine Tuning ◽  
Cyanine Dye ◽  
Thiazole Orange ◽  
Absorption And Emission ◽  
Donor And Acceptor ◽  
Dye Absorption ◽  
Donor Acceptor ◽  
Electron Donor And Acceptor

Strategically placed electron donor and acceptor groups allow fine-tuning of cyanine dye absorption and emission spectra while preserving recognition of biomolecular hosts such as DNA and proteins.

Novel quinoxalinone-based push–pull chromophores with highly sensitive emission and absorption properties towards small structural modifications

2018 ◽  
Vol 20 (33) ◽  
pp. 21515-21527 ◽  
Author(s):  
T. I. Burganov ◽  
S. A. Katsyuba ◽  
S. M. Sharipova ◽  
A. A. Kalinin ◽  
A. Monari ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Photophysical Properties ◽  
Visible Spectrum ◽  
Absorption Properties ◽  
Chemical Methods ◽  
Structural Modifications ◽  
Quantum Chemical Methods ◽  
Highly Sensitive

The photophysical properties of a series of novel push–pull quinoxalinone-based chromophores that strongly absorb and emit light in the broad visible spectrum were comprehensively studied both experimentally and through quantum chemical methods.

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