Nonplanar Donor–Acceptor Chiral Molecules with Large Second-Order Optical Nonlinearities: 1,1,4,4-Tetracyanobuta-1,3-diene Derivatives

Perspectives on push-pull chromophores derived from click-type [2 + 2] cycloaddition-retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

Various push-pull chromophores can be synthesized in a single and atom-economical step through [2 + 2] cycloaddition-retroelectrocyclization (CA-RE) reactions involving diverse electron-rich alkynes and electron-deficient alkenes. In this review, a comprehensive investigation of the recent and noteworthy advancements in the research on push-pull chromophores prepared via the [2 + 2] CA-RE reaction is conducted. In particular, an overview of the physicochemical properties of the family of these compounds that have been investigated is provided to clarify their potential for future applications.

Optical and electrochemical properties of spirobifluorene iridanaphthalene complexes

Three new spirobifluorene iridaaromatic compounds bearing electron-withdrawing or electron-donor substituents or another iridanaphthalene moiety have been synthesized and structurally characterized. Thorough experimental and theoretical evaluation revealed that these novel systems present a high thermal, air and electrochemical stability as well as low optical and electronic energy gap values with a significant redshift of the absorption maximum in the UV-Vis spectra and predicted remarkably higher first hyperpolarizabilities compared to their organic counterparts. Therefore, the combination of a metallaaromatic system with a spirobifluorene moiety leads to the design and development of new spirobifluorene derivatives. These new systems have shown interesting optical and electronic properties making them of interest for future applications in optoelectronics.

Electronic structure and second-order nonlinear optical property of chiral peropyrenes

Discovery of novel materials with excellent second-order nonlinear optical (NLO) properties is a very attractive topic in chemistry and materials science. Recently, much more attention has been paid to chiral compounds due to their inherent asymmetric structure and intramolecular charge transfer. Currently, the density functional theory (DFT) has become a powerful methodology to rationalize experimental observations and to design new materials with desirable properties. In this work, on the basis of the reported chiral peropyrene, we designed another five compounds consisting of donor or acceptor moieties and the donor/acceptor combinations. We systematically studied their geometrical/electronic structures and electronic transition/second-order NLO properties. The measured UV-Vis/CD spectra of compound 1 are almost reproduced by our calculations, enabling us to assign its electronic transition property and absolute configuration. For these compounds, the different substituents have great effect on their photophysical properties (i.e., band gap, absorption wavelength, and NLO response). The charge transfer synergy provides some useful information for further performance improvement. Interestingly, compound 6 shows a remarkably large first hyperpolarizability value of 18.14 × 10^-30 esu. Our research enables an opportunity for understanding the structure-property relationship of chiral peropyrenes. Graphical abstract The nonlinear optical properties of the studied compounds were studied with the aid of the DFT calculations.

Understanding the photophysical properties of chiral dinuclear Re(i) complexes and the role of Re(i) in their complexes

We have investigated the electronic structure, UV-Vis/CD spectra and the second-order NLO properties of chiral dinuclear Re(i) complexes and elucidated structure–property relationships with the aid of DFT calculations.

Photophysical properties of quinoxaline-fused [7]carbohelicene derivatives

The electronic circular dichroism, UV-Vis absorption, nonlinear optics, and charge transport properties of novel quinoxaline-fused 7-carbohelicene derivatives have been investigated for the first time.

Tetrathiafulvalene derivatives as cation sensor: density functional theory investigation of the hyper-Rayleigh scattering first hyperpolarizability

The hyper-Rayleigh scattering first hyperpolarizability of a series of extended tetrathiafulvalene (TTF) and TTF derivatives have been theoretically investigated using density functional theory to explore their use as potential cation sensor.