Role of Host–Guest Interactions in Tuning the Optical Properties of Coumarin Derivatives Incorporated in MCM-41: A TD-DFT Investigation

2012 ◽  
Vol 116 (33) ◽  
pp. 17807-17818 ◽  
Author(s):  
Alfonso Pedone ◽  
Julien Bloino ◽  
Vincenzo Barone
2020 ◽  
Vol 22 (48) ◽  
pp. 28230-28237
Author(s):  
Min Yang ◽  
Zan Lian ◽  
Chaowei Si ◽  
Bo Li

The tunable electronic and optical properties of graphene quantum dots achieved by nitrogen doping


2020 ◽  
Author(s):  
Tulin Okbinoglu ◽  
Pierre Kennepohl

Molecules containing sulfur-nitrogen bonds, like sulfonamides, have long been of interest due to their many uses and chemical properties. Understanding the factors that cause sulfonamide reactivity is important, yet their continues to be controversy regarding the relevance of S-N π bonding in describing these species. In this paper, we use sulfur K-edge x-ray absorption spectroscopy (XAS) in conjunction with density functional theory (DFT) to explore the role of S<sub>3p</sub> contributions to π-bonding in sulfonamides, sulfinamides and sulfenamides. We explore the nature of electron distribution of the sulfur atom and its nearest neighbors and extend the scope to explore the effects on rotational barriers along the sulfur-nitrogen axis. The experimental XAS data together with TD-DFT calculations confirm that sulfonamides, and the other sulfinated amides in this series, have essentially no S-N π bonding involving S<sub>3p</sub> contributions and that electron repulsion and is the dominant force that affect rotational barriers.


Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2349
Author(s):  
Alain Salvador Conejo-Dávila ◽  
Marco Armando Moya-Quevedo ◽  
David Chávez-Flores ◽  
Alejandro Vega-Rios ◽  
Erasto Armando Zaragoza-Contreras

The development of anilinium 2-acrylamide-2-methyl-1-propanesulfonate (Ani-AMPS) monomer, confirmed by 1H NMR, 13C NMR, and FTIR, is systematically studied. Ani-AMPS contains two polymerizable functional groups, so it was submitted to selective polymerization either by free-radical or oxidative polymerization. Therefore, poly(anilinium 2-acrylamide-2-methyl-1-propanesulfonic) [Poly(Ani-AMPS)] and polyaniline doped with 2-acrylamide-2-methyl-1-propanesulfonic acid [PAni-AMPS] can be obtained. First, the acrylamide polymer, poly(Ani-AMPS), favored the π-stacking of the anilinium group produced by the inter- and intra-molecular interactions and was studied utilizing 1H NMR, 13C NMR, FTIR, and UV-Vis-NIR. Furthermore, poly(Ani-AMPS) fluorescence shows quenching in the presence of Fe2+ and Fe3+ in the emission spectrum at 347 nm. In contrast, the typical behavior of polyaniline is observed in the cyclic voltammetry analysis for PAni-AMPS. The optical properties also show a significant change at pH 4.4. The PAni-AMPS structure was corroborated through FTIR, while the thermal properties and morphology were analyzed utilizing TGA, DSC (except PAni-AMPS), and FESEM.


RSC Advances ◽  
2021 ◽  
Vol 11 (14) ◽  
pp. 7961-7971
Author(s):  
N. D. Vinh ◽  
P. M. Tan ◽  
P. V. Do ◽  
S. Bharti ◽  
V. X. Hoa ◽  
...  

The role of samarium (Sm) dopant on the structural, morphological, and optical properties of CdS QDs and CdS/ZnS core/shell QDs was methodically reported.


2020 ◽  
Vol 281 ◽  
pp. 121028 ◽  
Author(s):  
Saad Mabrouk Yakout ◽  
Hanan A. Mousa ◽  
Hala T. Handal ◽  
Walid Sharmoukh

2010 ◽  
Vol 247 (8) ◽  
pp. 1960-1964 ◽  
Author(s):  
Conor Hogan ◽  
Rita Magri ◽  
Rodolfo Del Sole

Sign in / Sign up

Export Citation Format

Share Document