Relationship between Metallophilic Interactions and Luminescent Properties in Pt(II) Complexes: TD-DFT Guide for the Molecular Design of Light-Responsive Materials

2016 ◽  
Vol 120 (3) ◽  
pp. 2002-2012 ◽  
Author(s):  
Julia Romanova ◽  
M. R. Ranga Prabhath ◽  
Peter D. Jarowski
2016 ◽  
Vol 2 (1) ◽  
pp. e1501297 ◽  
Author(s):  
Qian Zhao ◽  
Weike Zou ◽  
Yingwu Luo ◽  
Tao Xie

Stimuli-responsive materials with sophisticated yet controllable shape-changing behaviors are highly desirable for real-world device applications. Among various shape-changing materials, the elastic nature of shape memory polymers allows fixation of temporary shapes that can recover on demand, whereas polymers with exchangeable bonds can undergo permanent shape change via plasticity. We integrate the elasticity and plasticity into a single polymer network. Rational molecular design allows these two opposite behaviors to be realized at different temperature ranges without any overlap. By exploring the cumulative nature of the plasticity, we demonstrate easy manipulation of highly complex shapes that is otherwise extremely challenging. The dynamic shape-changing behavior paves a new way for fabricating geometrically complex multifunctional devices.


2021 ◽  
Author(s):  
Kevin Greenman ◽  
William Green ◽  
Rafael Gómez-Bombarelli

Optical properties are central to molecular design for many applications, including solar cells and biomedical imaging. A variety of ab initio and statistical methods have been developed for their prediction, each with a trade-off between accuracy, generality, and cost. Existing theoretical methods such as time-dependent density functional theory (TD-DFT) are generalizable across chemical space because of their robust physics-based foundations but still exhibit random and systematic errors with respect to experiment despite their high computational cost. Statistical methods can achieve high accuracy at a lower cost, but data sparsity and unoptimized molecule and solvent representations often limit their ability to generalize. Here, we utilize directed message passing neural networks (D-MPNNs) to represent both dye molecules and solvents for predictions of molecular absorption peaks in solution. Additionally, we demonstrate a multi-fidelity approach based on an auxiliary model trained on over 28,000 TD-DFT calculations that further improves accuracy and generalizability, as shown through rigorous splitting strategies. Combining several openly-available experimental datasets, we benchmark these methods against a state-of-the-art regression tree algorithm and compare the D-MPNN solvent representation to several alternatives. Finally, we explore the interpretability of the learned representations using dimensionality reduction and evaluate the use of ensemble variance as an estimator of the epistemic uncertainty in our predictions of molecular peak absorption in solution. The prediction methods proposed herein can be integrated with active learning, generative modeling, and experimental workflows to enable the more rapid design of molecules with targeted optical properties.


2021 ◽  
Author(s):  
Narissa Kanlayakan ◽  
Nawee Kungwan

A molecular screening for fluorescent probes harnessing excited-stated intramolecular proton transfer (ESIPT) of NH-type molecules having aminophenyl or tosylaminophenyl as a proton donor and benzimidazole, benzoxazole, benzothiazole, or imidazo[1,2-a]pyridine as...


Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2027
Author(s):  
Nan Gao ◽  
Xiaochen Lin ◽  
Jinglin Liu ◽  
Yuanzuo Li ◽  
Yanhui Yang

This paper theoretically simulated (using DFT and TD-DFT in N,N-dimethylformamide (DMF) solvent) the photodynamic properties of three non-metallic dye molecules with D-π-A1-π-A2 structure. The total photoelectric conversion efficiency (PCE) could be evaluated by the following parameters: the geometric structures, the electronic structures, and the absorption spectra, the analyses of charge difference density (CDD) and natural bond orbitals (NBO), the analyses of ionization potential (IP) and electron affinity (EA) from electronic contribution capacity, the reorganization energies (λh, λe, and λtotal), and the chemical reaction parameter (h, ω, ω-, and ω+) for intramolecular charge transfer (ICT) processing, the excited lifetime (τ) and the vertical dipole moment (μnormol). The ∆Ginject, the ∆Gdyeregen, the light harvesting efficiencies (LHE) and the excited lifetime (τ) were used to explain experimental JSC. The experimental trend of VOC was explained by the calculation of ∆ECB and μnormol. Moreover, the 15 dyes were designed by adding the electron-donor groups (–OH, –NH2, and –OCH3) and the electron-acceptor groups (–CF3, –F, and −CN) to the LS-387 molecular skeleton, which improved electronic contribution, intramolecular charge transfer (ICT), and optoelectronic performance.


2003 ◽  
Vol 771 ◽  
Author(s):  
Jae Buem Oh ◽  
Kyung Lim Paik ◽  
Jae-Won Ka ◽  
Soo-Gyun Roh ◽  
Min Kook Nah ◽  
...  

AbstractWe have investigated the development of erbium(III)-cored supramolecular complexes containing metalloporphyrins to circumvent the solubility problem and improve the optical amplification property. The new synthetic methodology was accomplished through the ligand-exchange model reaction using ErCl3 to optimize its synthetic condition We have designed and synthesized the model complexes to investigate coordination property between the ligand and the erbium ion. Highly coordinated erbium(III)-cored model complexes (at least 8 to 10 coordination) showed the strong near infrared(IR) emission at 1520 nm, corresponding to the 4I13/2 → 4I15/2 transition. Also, with these synthetic results, erbium(III)-cored supramolecular complexes based on metalloporphyrins were synthesized and characterized. They also showed the infrared emission of the 4I13/2 → 4I15/2 transition at 1520 nm.


Author(s):  
Edison Rafael Jimenez ◽  
Manuel Caetano ◽  
Nelson Santiago ◽  
F. Javier Torres ◽  
Thibault Terencio ◽  
...  

Since the discovery of the aggregation-induced emission effect in 2001, diaminodicyanoquinone derivatives (DADQs) have presented interesting fluorescence properties, allowing them to be considered fluorescent dyes capable of showing quantum yields above 90%. Besides, the diaminodiacyanoquinone core represents a versatile building block propense either to modification or integration into different systems to obtain and provide them unique photophysical features. Herein, we carried out a theoretical study on the fluorescence properties of three different diaminodicyanoquinodimethane systems. Therefore, time-dependent density functional theory (TD-DFT) was used to obtain the values associated with the dipole moments, oscillator strengths, and the conformational energies between the ground and the first excited states of each molecule. The results suggest that only two of the three studied systems possess significant luminescent properties. In a further stage, the theoretical insights were confirmed by means of experimental measurements, which not only retrieved the luminescence of the DADQs, but also suggest a preliminary and promising antibacterial activity of these systems.


2008 ◽  
Vol 80 (7) ◽  
pp. 1525-1538 ◽  
Author(s):  
Alexander A. Ishchenko

The advantages of dye-doped polymer matrices over polymers and dyes, separately, are analyzed. The effects of the polymer nature and chemical constitution of organic dyes on the spectral and luminescent properties of these matrices are discussed. The processes of dye aggregation in polymers are characterized, and their influence on the photophysical properties and photochemical stability of dye-doped nonphotoconducting and photoconducting polymers is discussed. The different approaches for the struggle with dye aggregation in polymers are offered. The main paths of energy degradation of electronic excitation in such materials are analyzed. The prospects for the applications of dye-doped polymer materials as passive Q-switches of solid-state lasers, active laser media (ALM), luminescent solar concentrator (LSCs), photovoltaic cells, and electroluminescent (EL) emitters are demonstrated.


2021 ◽  
Vol 22 (1) ◽  
pp. 446
Author(s):  
Edison Rafael Jiménez ◽  
Manuel Caetano ◽  
Nelson Santiago ◽  
F. Javier Torres ◽  
Thibault Terencio ◽  
...  

Recently, several studies have demonstrated that diaminodicyanoquinone derivatives (DADQs) could present interesting fluorescence properties. Furthermore, some DADQs under the solid state are capable of showing quantum yields that can reach values of 90%. Besides, the diaminodiacyanoquinone core represents a versatile building block propense either to modification or integration into different systems to obtain and provide them unique photophysical features. Herein, we carried out a theoretical study on the fluorescence properties of three different diaminodicyanoquinodimethane systems. Therefore, time-dependent density functional theory (TD-DFT) was used to obtain the values associated with the dipole moments, oscillator strengths, and the conformational energies between the ground and the first excited states of each molecule. The results suggest that only two of the three studied systems possess significant luminescent properties. In a further stage, the theoretical insights were confirmed by means of experimental measurements, which not only retrieved the photoluminescence of the DADQs, but also suggest a preliminary and promising antibacterial activity of these systems.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhiwei Zhang ◽  
Wenhui Wang ◽  
Peipei Jin ◽  
Jiadan Xue ◽  
Lu Sun ◽  
...  

Abstract Current development of light-responsive materials and technologies imposes an urgent demand on visible-light photoswitching on account of its mild excitation with high penetration ability and low photo-toxicity. However, complicated molecular design and laborious synthesis are often required for visible-light photoswitch, especially for diarylethenes. Worse still, a dilemma is encountered as the visible-light excitation of the diarylethene is often achieved at the expense of photochromic performances. To tackle these setbacks, we introduce a building-block design strategy to achieve all-visible-light photochromism with the triplet-sensitization mechanism. The simply designed diarylethene system is constructed by employing a sensitizer building-block with narrow singlet-triplet energy gap (ΔEST) to a diarylethene building-block. A significant improvement on the photochromic efficiency is obtained as well as an enhanced photo-fatigue resistance over those under UV irradiation. The balance between the visible-light excitation and decent photochromism is thus realized, promoting a guiding principle for the visible-light photochromism.


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