Synthesis and Optical Properties of Donor–Acceptor-Type 1,3,5,9-Tetraarylpyrenes: Controlling Intramolecular Charge-Transfer Pathways by the Change of π-Conjugation Directions for Emission Color Modulations

Solvents play an important role in shaping the intramolecular charge transfer (ICT) properties of π-conjugated molecules, which in turn can affect their one-photon absorption (OPA) and two-photon absorption (TPA) as well as the static (hyper)polarizabilities. Here, we study the effect of solvent and donor-acceptor arrangement on linear and nonlinear optical (NLO) response properties of two novel ICT-based fluorescent sensors, one consisting of hemicyanine and dimethylaniline as electron withdrawing and donating groups (molecule 1), respectively and its boron-dipyrromethene (BODIPY, molecule 2)-fused counterpart (molecule 3). Density functional theoretical (DFT) calculations using long-range corrected CAM-B3LYP and M06-2X functionals, suitable for studying properties of ICT molecules, are employed to calculate the desired properties. The dipole moment (µ) as well as the total first hyperpolarizability (βtotal) of the studied molecules in the gas phase is dominantly dictated by the component in the direction of charge transfer. The ratios of vector component of first hyperpolarizability (βvec) to βtotal also reveal unidirectional charge transfer process. The properties of the medium significantly affect the OPA, hyperpolarizability and TPA properties of the studied molecules. Time dependent DFT (TDDFT) calculations suggest interchanging between two lowest excited states of molecule 3 from the gas phase to salvation. The direction of charge polarization and dominant transitions among molecular orbitals involved in the OPA and TPA processes are studied. The results presented are expected to be useful in tuning the NLO response of many ICT-based chromophores, especially those with BODIPY acceptors.

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Tetraphenylethenyl-Modified 1,8-Naphthalimide Dye with Efficient Aggregation-Enhanced Emisssion, Solvatochromism and Intramolecular Charge Transfer Characteristics

Journal of Physics Conference Series ◽

10.1088/1742-6596/2109/1/012025 ◽

2021 ◽

Vol 2109 (1) ◽

pp. 012025

Author(s):

Qiuli Zhao ◽

Qinghao Yang

Keyword(s):

Charge Transfer ◽

Intramolecular Charge Transfer ◽

Quantum Yields ◽

Transfer Property ◽

Organic Luminophores ◽

Emission Color ◽

High Fluorescence ◽

Photo Stability ◽

Chemical Fields ◽

Naphthalimide Dye

Abstract 1,8-naphthalimide (NI) dyes are one class of important organic luminophores with good photo-stability, high fluorescent quantum yields and broad emission color-tunability, which are widely used in biological and chemical fields. However, they exhibit bad ACQ property, which heavily limits their application in real word. Contrary to ACQ, tetraphenylethene (TPE) is an AIE luminogen. To eliminate the ACQ effect of NI, TPE was used as core and NI chromophores was used as peripheries to obtain a new dye TPEDNI. TPEDNI dye demonstrates typical aggregation-enhanced emission (AEE) characteristic with high fluorescence Φ>F, solid up to 100% in the film state, which is 24 times of that for its THF solution. Besides, TPEDNI exhibits marked solvatochromism, and the emission peak red-shifts from 505 nm in hexane to 610 nm in acetonitrile. TPENI also displays evident intramolecular charge transfer property in THF/water mixtures

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Non-Adiabatic Photoprocesses of Fundamental Importance to Chemistry: From Electronic Relaxation of DNA Bases to Intramolecular Charge Transfer in Electron Donor-Acceptor Molecules

Challenges and Advances In Computational Chemistry and Physics - Radiation Induced Molecular Phenomena in Nucleic Acids ◽

10.1007/978-1-4020-8184-2_15 ◽

2008 ◽

pp. 395-433

Author(s):

Marek Z. Zgierski ◽

Takashige Fujiwara ◽

Edward C. Lim

Keyword(s):

Charge Transfer ◽

Electron Donor ◽

Intramolecular Charge Transfer ◽

Dna Bases ◽

Fundamental Importance ◽

Electronic Relaxation ◽

Donor Acceptor ◽

Acceptor Molecules

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Effects of molecular geometry on the efficiency of intramolecular charge transfer–based luminescence in o-carboranyl-substituted 1H-phenanthro[9,10-d]imidazoles

Inorganic Chemistry Frontiers ◽

10.1039/d1qi01405f ◽

2022 ◽

Author(s):

Sehee Im ◽

Chan Hee Ryu ◽

Mingi Kim ◽

Dong Kyun You ◽

Sanghee Yi ◽

...

Keyword(s):

Optical Properties ◽

Charge Transfer ◽

Phenyl Ring ◽

Intramolecular Charge Transfer ◽

Molecular Geometry

Herein, we compared the optical properties of four compounds with an o-carborane cage linked to 1H-phenanthro[9,10-d]imidazole at the ortho- (oPC), meta- (mPC), or para-position (pPC) of the 2-phenyl ring or...

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