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Guankui Long Yecheng Zhou Mingtao Zhang Randy Sabatini Abdullah Rasmita Li Huang Girish Lakhwani Weibo Gao 《Advanced materials (Deerfield Beach, Fla.)》2019,31(17)
Hybrid organic–inorganic perovskites (HOIPs), in particular 3D HOIPs, have demonstrated remarkable properties, including ultralong charge‐carrier diffusion lengths, high dielectric constants, low trap densities, tunable absorption and emission wavelengths, strong spin–orbit coupling, and large Rashba splitting. These superior properties have generated intensive research interest in HOIPs for high‐performance optoelectronics and spintronics. Here, 3D hybrid organic–inorganic perovskites that implant chirality through introducing the chiral methylammonium cation are demonstrated. Based on structural optimization, phonon spectra, formation energy, and ab initio molecular dynamics simulations, it is found that the chirality of the chiral cations can be successfully transferred to the framework of 3D HOIPs, and the resulting 3D chiral HOIPs are both kinetically and thermodynamically stable. Combining chirality with the impressive optical, electrical, and spintronic properties of 3D perovskites, 3D chiral perovskites is of great interest in the fields of piezoelectricity, pyroelectricity, ferroelectricity, topological quantum engineering, circularly polarized optoelectronics, and spintronics. 相似文献
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Ed W.B de Leer 《Water research》1985,19(11):1411-1419
In harbour sediment samples taken near an epichlorohydrin production plant, a series of highly chlorinated ethers and diethers were detected viz. three isomeric bis(dichloropropyl)ethers, several structurally closely related ethers with 9 carbon atoms (C9 ethers), a number of C12 ethers and diethers, and finally several C15 ethers. The formation of this new class of ether compounds can be explained on the basis of the chemistry of the addition of HOCl to allylchloride. After initial addition of Cl−, a reactive intermediate is formed which may react with the product dichloropropanol, to give the C6 ethers, or may polymerize with the starting compound allylchloride followed by reaction with the product, to give the C9, C12 and C15 ethers. 相似文献
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Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu^2 at different pH values were studied in a water/alcohol two-phase system containing Cu^2 and N-ndodecyl-L-proline(A). The influences of the solvent sort, the pH value, the concentrations of Cu^2 and chiral ligand on the partition coefficient(K) and separation factor(α) were discussed. The experimental results show that the A formed has more stable ternary complex with D-mandelic acid enantiomer than with L-mandelic acid enantiomer. There is an important influence of the pH value on K and a. When the pH values are less than 3.5, the formation of binary complexes is thermodynamically unfavourable. K and a become maximum when pH values are above 3.5 and the molar ratio of the chiral ligand to Cu^2 is 2:1. 相似文献
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Using the photonic band gap in photonic crystals, the fundamental waveguide structures for the light wavelength range have been developed. Based on the fine structure of these many functional devices have been proposed by analytical or numerical simulation methods and the experiments of trial manufacture. In this paper, the treatment of chiral dielectric in the Condensed Node Spatial Network for the vector potential is explained, and we show the polarization plane rotation property in air‐hole and pillar type photonic crystal waveguide structures with the chiral medium substrate. Then, we show the fundamental advantage of the air‐hole type photonic crystal waveguide structure in application to a mode converter. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(1): 7–14, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20098 相似文献
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Aleksandra A. Ageeva Ilya M. Magin Alexander B. Doktorov Victor F. Plyusnin Polina S. Kuznetsova Alexander A. Stepanov Alexander A. Alekseev Nikolay E. Polyakov Tatyana V. Leshina 《International journal of molecular sciences》2021,22(12)
The study of the L- and D-amino acid properties in proteins and peptides has attracted considerable attention in recent years, as the replacement of even one L-amino acid by its D-analogue due to aging of the body is resulted in a number of pathological conditions, including Alzheimer’s and Parkinson’s diseases. A recent trend is using short model systems to study the peculiarities of proteins with D-amino acids. In this report, the comparison of the excited states quenching of L- and D-tryptophan (Trp) in a model donor–acceptor dyad with (R)- and (S)-ketoprofen (KP-Trp) was carried out by photochemically induced dynamic nuclear polarization (CIDNP) and fluorescence spectroscopy. Quenching of the Trp excited states, which occurs via two mechanisms: prevailing resonance energy transfer (RET) and electron transfer (ET), indeed demonstrates some peculiarities for all three studied configurations of the dyad: (R,S)-, (S,R)-, and (S,S)-. Thus, the ET efficiency is identical for (S,R)- and (R,S)-enantiomers, while RET differs by 1.6 times. For (S,S)-, the CIDNP coefficient is almost an order of magnitude greater than for (R,S)- and (S,R)-. To understand the source of this difference, hyperpolarization of (S,S)-and (R,S)- has been calculated using theory involving the electron dipole–dipole interaction in the secular equation. 相似文献
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乙基乙烯基酮与4,4-乙二氧撑-2-甲基环乙酮2 c的手性亚胺进行不对称Michael加成,生成2,2-双取代环烷酮5,5经过克莱森缩合得到(-)-6,6-乙二氧撑-1,10-二甲基-1(9)-八氢萘酮-2(-)(1 c)。 相似文献
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