scholarly journals Triphenylamine-Merocyanine-Based D1-A1-π-A2/A3-D2 Chromophore System: Synthesis, Optoelectronic, and Theoretical Studies

2019 ◽  
Vol 20 (7) ◽  
pp. 1621 ◽  
Author(s):  
Pedada Srinivasa Rao ◽  
Avinash L. Puyad ◽  
Sidhanath V. Bhosale ◽  
Sheshanath V. Bhosale
Keyword(s):  
Charge Transfer ◽  
Small Molecules ◽  
Intramolecular Charge Transfer ◽  
Energy Levels ◽  
Fluorescence Emission ◽  
Theoretical Studies ◽  
Computational Studies ◽  
Lumo Energy ◽  
Strong Electron ◽  
System Synthesis

donor–acceptorDonor–acceptor–π–acceptor–donor (D1-A1-π-A2/A3-D2)-type small molecules, such TPA-MC-2 and TPA-MC-3, were designed and synthesized starting from donor-substituted alkynes (TPA-MC-1) via [2 + 2] cycloaddition−retroelectrocyclization reaction with tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) units, respectively. TPA-MC-2 and TPA-MC-3 chromophores differ on the A2/A3 acceptor subunit, which is 1,1,4,4-tetracyanobutadiene (TCBD) and a dicyanoquinodicyanomethane (DCQDCM), respectively. Both the derivative bearing same donors D1 (triphenylamine) and D2 (trimethylindolinm) and also same A1 (monocyano) as an acceptor, tetracyano with an aryl rings as the π-bridging moiety. The incorporation of TCNE and TCNQ as strong electron withdrawing units led to strong intramolecular charge-transfer (ICT) interactions, resulting in lower LUMO energy levels. Comparative UV–Vis absorption, fluorescence emission, and electrochemical and computational studies were performed to understand the effects of the TCNE and TCNQ subunits incorporated on TPA-MC-2 and TPA-MC-3, respectively.

scholarly journals Synthesis and Properties of D–π–A Structural Imidazole-Triphenylamine Derivatives

2018 ◽  
Vol 42 (1) ◽  
pp. 20-23 ◽  
Author(s):  
Hua-Nan Peng ◽  
Ye Yu ◽  
Xiao-Hui Liu ◽  
Jie Zheng ◽  
Hao Cheng ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Optical Properties ◽  
Charge Transfer ◽  
Intramolecular Charge Transfer ◽  
Electrochemical Behaviour ◽  
Energy Levels ◽  
Electrochemical Measurements ◽  
Lumo Energy ◽  
Homo And Lumo ◽  
Homo And Lumo Energy

Four novel D-π-A structural 1-aryl-2-[4-(N,N-diphenyl)phenyl]-4,5-diphenyl-1H-imidazoles have been synthesised. Their synthesis, thermal stability, optical properties and electrochemical behaviour have also been investigated. These compounds exhibit increased thermal stability, blue emissions and intramolecular charge transfer. The HOMO and LUMO energy levels of these compounds were calculated from electrochemical measurements.

π-Bridge modification of thiazole-bridged DPP polymers for high performance near-IR OSCs

2018 ◽  
Vol 20 (3) ◽  
pp. 1664-1672 ◽  
Author(s):  
Kuangshi Sun ◽  
Xiaoqin Tang ◽  
Yalin Ran ◽  
Rongxing He ◽  
Wei Shen ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Charge Transport ◽  
Transport Properties ◽  
High Performance ◽  
Intramolecular Charge Transfer ◽  
Energy Levels ◽  
Near Ir

π-Bridge modification could adjust the molecular energy levels and improve the optical, intramolecular charge transfer and charge transport properties.

Dehydrogenation induced inhibition of intramolecular charge transfer in substituted pyrazoline analogues

2017 ◽  
Vol 19 (19) ◽  
pp. 11937-11946 ◽  
Author(s):  
Pronab Kundu ◽  
Dipanwita Banerjee ◽  
Gourhari Maiti ◽  
Nitin Chattopadhyay
Keyword(s):  
Excited State ◽  
Charge Transfer ◽  
Intramolecular Charge Transfer ◽  
Computational Studies ◽  
Pyrazoline Ring

Experimental and computational studies reveal that dehydrogenation of the pyrazoline ring modifies its ground and excited state photophysics radically by restricting the ICT process.

scholarly journals Donor-acceptor substituted phenylethynyltriphenylenes – excited state intramolecular charge transfer, solvatochromic absorption and fluorescence emission

2010 ◽  
Vol 6 ◽  
pp. 992-1001 ◽  
Author(s):  
Ritesh Nandy ◽  
Sethuraman Sankararaman
Keyword(s):  
Excited State ◽  
Charge Transfer ◽  
Linear Correlation ◽  
Intramolecular Charge Transfer ◽  
Stokes Shift ◽  
Fluorescence Emission ◽  
Solvent Polarity ◽  
Donor And Acceptor ◽  
Electron Donor And Acceptor ◽  
Stokes Shifts

Several 2-(phenylethynyl)triphenylene derivatives bearing electron donor and acceptor substituents on the phenyl rings have been synthesized. The absorption and fluorescence emission properties of these molecules have been studied in solvents of different polarity. For a given derivative, solvent polarity had minimal effect on the absorption maxima. However, for a given solvent the absorption maxima red shifted with increasing conjugation of the substituent. The fluorescence emission of these derivatives was very sensitive to solvent polarity. In the presence of strongly electron withdrawing (–CN) and strongly electron donating (–NMe2) substituents large Stokes shifts (up to 130 nm, 7828 cm−1) were observed in DMSO. In the presence of carbonyl substituents (–COMe and –COPh), the largest Stokes shift (140 nm, 8163 cm−1) was observed in ethanol. Linear correlation was observed for the Stokes shifts in a Lippert–Mataga plot. Linear correlation of Stokes shift was also observed with E T(30) scale for protic and aprotic solvents but with different slopes. These results indicate that the fluorescence emission arises from excited state intramolecular charge transfer in these molecules where the triphenylene chromophore acts either as a donor or as an acceptor depending upon the nature of the substituent on the phenyl ring. HOMO–LUMO energy gaps have been estimated from the electrochemical and spectral data for these derivatives. The HOMO and LUMO surfaces were obtained from DFT calculations.

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