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Substituent

About: Substituent is a research topic. Over the lifetime, 42877 publications have been published within this topic receiving 516716 citations. The topic is also known as: side chain & side group.


Papers
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Journal ArticleDOI
Abstract: Low bandgap and two-dimensional (2D)-conjugated copolymers based on benzo[1,2-b:4,5-b′]dithiophene with conjugated thiophene side chains (BDTT) and thieno[3,4-b]thiophene with electron-withdrawing substituents (TT) are attractive high efficiency polymer donor materials in polymer solar cells (PSCs). In this work, we introduced an alkylthio substituent on the thiophene side chain in the polymer and synthesized a new low bandgap 2D-conjugated polymer PBDTT-S-TT. The alkylthio substituent increased the hole mobility of the polymer to 4.08 × 10−3 cm2 V−1 s−1 and down-shifted the HOMO energy level of the polymer by 0.11 eV with absorption of the polymer film red-shifted slightly. The PSCs based on PBDTT-S-TT as a donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM) as an acceptor without solvent additive treatment demonstrated a high open-circuit voltage (Voc) of 0.84 V, leading to a high power conversion efficiency (PCE) of 8.42%, under the illumination of AM 1.5 G 100 mW cm−2. For comparison, the Voc and PCE of the devices based on the corresponding parent polymer PBDTT-TT with the device optimization of 3% DIO additive treatment are 0.77 V and 7.38%, respectively. The enhanced Voc value of 0.84 V for the PSC based on PBDTT-S-TT should be benefited from the down-shifted HOMO energy level of the polymer. The results indicate that the alkylthio substitution is an effective way to further improve the photovoltaic performance of the 2D-conjugated polymer donor materials in PSCs.

484 citations

Patent
26 Nov 2002
TL;DR: In this paper, an organic electroluminescenters with an organic layer clamped between two electrodes contains a compound expressed by a general formula (1) in at least one layer of the organic layer.
Abstract: PROBLEM TO BE SOLVED: To provide an organic electroluminescent element of excellent luminous efficiency with a long service life, and a display device of low power consumption with a long service life using the organic electroluminescent element. SOLUTION: This organic electroluminescent element with an organic layer clamped between two electrodes contains a compound expressed by a general formula (1), in at least one layer of the organic layer. In the formula, B represents a boron atom, C represents a carbon atom, A11 , A12 and A13 represent a carbon atom or a nitrogen atom, Z11 , Z12 and Z13 represent an atomic group required to complete an aromatic ring, R11 , R12 and R13 independently represent an alkyl group, an alkyloxy group, an aryloxy group or an halogen atom, R14 , R15 and R16 independently represent a hydrogen atom or a monovalent substituent, and l, m, n independently represent 0-7.

482 citations

Journal ArticleDOI
TL;DR: In this paper, a brief analysis of the current understanding of substituent perturbations in monosubstituted benzenes as determined by substituents induced carbon chemical shifts is presented.
Abstract: A brief analysis is presnted of the current understanding of substituent perturbations in monosubstituted benzenes as determined by substituent induced carbon chemical shifts. A critical tabulation of the four substituent chemical shifts is given for c. 700 monosubstituted benzenes.

460 citations

Book
20 Feb 2007
TL;DR: The Nature and Analysis of Substituent Electronic Effects Substituents on Ground-State Molecular Structures and Charge Distributions Some Theoretical Studies of Electronic Substituant Effects in Organic Chemistry Electronic Substitent Effects in Molecular Spectroscopy Superbasic Ion Pairs: Alkali Metal Salts of Alkylarenes A General Treatment of Electrical Effects.
Abstract: The Nature and Analysis of Substituent Electronic Effects Substituent Effects on Ground-State Molecular Structures and Charge Distributions Some Theoretical Studies of Electronic Substituent Effects in Organic Chemistry Electronic Substituent Effects in Molecular Spectroscopy Superbasic Ion Pairs: Alkali Metal Salts of Alkylarenes A General Treatment of Electrical Effects.

460 citations

Journal ArticleDOI
22 Feb 1985-Science
TL;DR: The only role thus far identified for coenzyme B12 in these reactions--namely, that of a free radical precursor--reflects the weakness, and facile dissociation, of the cobalt-carbon bond.
Abstract: Coenzyme B12 serves as a cofactor in various enzymatic reactions in which a hydrogen atom is interchanged with a substituent on an adjacent carbon atom. Measurement of the dissociation energy of the coenzyme's cobalt-carbon bond and studies of the rearrangement of model free radicals related to those derived from methylmalonyl-coenzyme A suggest that these enzymatic reactions occur through homolytic dissociation of the coenzyme's cobalt-carbon bond, abstraction of a hydrogen atom from the substrate by the coenzyme-derived 5'-deoxyadenosyl radical, and rearrangement of the resulting substrate radical. The only role thus far identified for coenzyme B12 in these reactions--namely, that of a free radical precursor--reflects the weakness, and facile dissociation, of the cobalt-carbon bond.

431 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023660
20221,273
2021568
2020787
2019753
2018858