Rational classification of a series of aromatic donor–acceptor systems within the twisting intramolecular charge transfer model, a time-dependent density-functional theory investigation

series of push-pull chromophores built around thiophene-based . π-conjugating spacers and bearing various types of amino-donors and cyanovinyl-acceptors have been analyzed by means of UV-Vis- NIR spectroscopic measurements. Density functional theory (DFT) calculations have also been performed to help the assignment of the most relevant electronic features and to derive useful information about the molecular structure of these NLO-phores. The effects of the donor/acceptor substitution in the electronic and molecular properties of the .π -conjugated spacer have been addressed. The effectiveness of the intramolecular charge transfer (ICT) has also been tested as a function of the nature of the end groups (i.e., electron-donating or electron-withdrawing capabilities).

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Assembly of New Merocyanine Chromophores with a 1,8-Naphthalimide Core by a New Method for the Synthesis of the Methine Function

Australian Journal of Chemistry ◽

10.1071/ch15139 ◽

2015 ◽

Vol 68 (9) ◽

pp. 1399 ◽

Cited By ~ 3

Author(s):

Aleksey A. Vasilev ◽

Stanislav Baluschev ◽

Diana Cheshmedzhieva ◽

Sonia Ilieva ◽

Obis D. Castaño ◽

...

Keyword(s):

Density Functional ◽

Intramolecular Charge Transfer ◽

Photophysical Properties ◽

Time Dependent ◽

New Method ◽

High Chemical ◽

Functional Theory ◽

Leaving Group ◽

Wavelength Absorption ◽

Positive Solvatochromism

A new method for the synthesis of the monomethine group using nitro as a leaving group in an SN-Ar reaction is described. A series of novel merocyanine dyes has been synthesised and their photophysical properties have been elucidated. The longest wavelength absorption occurs in the range 519–619 nm and the molar absorptivities vary with the substituents and are in the range 1000–47700 L mol–1 cm–1. The dyes show high chemical and photostability. One example from the series has the ability to distinguish methanol from ethanol. The introduction of a quinoid fragment into the structure leads to a pronounced intramolecular charge transfer and hence a noticeable positive solvatochromism. The structures and electronic properties of the compounds have been studied by density functional theory (DFT) and time-dependent DFT.

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Design of donor–acceptor copolymers for organic photovoltaic materials: a computational study

Physical Chemistry Chemical Physics ◽

10.1039/c7cp08176f ◽

2018 ◽

Vol 20 (5) ◽

pp. 3581-3591 ◽

Cited By ~ 20

Author(s):

Haydar Taylan Turan ◽

Oğuzhan Kucur ◽

Birce Kahraman ◽

Seyhan Salman ◽

Viktorya Aviyente

Keyword(s):

Density Functional ◽

Computational Study ◽

Time Dependent ◽

Organic Photovoltaic ◽

Functional Theory ◽

Organic Chromophores ◽

Photovoltaic Materials ◽

Td Dft ◽

Organic Photovoltaic Materials ◽

Donor Acceptor

80 different push–pull type organic chromophores which possess Donor–Acceptor (D–A) and Donor–Thiophene–Donor–Thiophene (D–T–A–T) structures have been systematically investigated by means of density functional theory (DFT) and time-dependent DFT (TD-DFT) at the B3LYP/6-311G* level.

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