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991.
992.
Back Cover: Multifunctional Tricarbazolo Triazolophane Macrocycles: One‐Pot Preparation,Anion Binding,and Hierarchical Self‐Organization of Multilayers (Chem. Eur. J. 2/2016) 下载免费PDF全文
993.
Exciton‐Vibrational Couplings in Homo‐ and Heterodimer Stacks of Perylene Bisimide Dyes within Cyclophanes: Studies on Absorption Properties and Theoretical Analysis 下载免费PDF全文
David Bialas Christoph Brüning Dr. Felix Schlosser Dr. Benjamin Fimmel Johannes Thein Prof. Dr. Volker Engel Prof. Dr. Frank Würthner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):15011-15018
The optical properties of a series of three cyclophanes comprising either identical or different perylene bisimide (PBI) chromophores were studied by UV/Vis absorption spectroscopy and their distinctive spectral features were analyzed. All the investigated cyclophanes show significantly different absorption features with respect to the corresponding constituent PBI monomers indicating strong coupling interactions between the PBI units within the cyclophanes. DFT calculations suggest a π‐stacked arrangement of the PBI units at close van der Waals distance in the cyclophanes with rotational displacement. Simulations of the absorption spectra based on time‐dependent quantum mechanics properly reproduced the experimental spectra, revealing exciton‐vibrational coupling between the chromophores both in homo‐ and heterodimer stacks. The PBI cyclophane comprising two different PBI chromophores represents the first example of a PBI heterodimer stack for which the exciton coupling has been investigated. The quantum dynamics analysis reveals that exciton coupling in heteroaggregates is indeed of similar strength as for homoaggregates. 相似文献
994.
Cover Picture: Nanoimprint texturing of transparent flexible substrates for improved light management in thin‐film solar cells (Phys. Status Solidi RRL 4/2015) 下载免费PDF全文
995.
Kinetics and Mechanism of the Reaction of a Ruthenium(VI) Nitrido Complex with HSO3− and SO32− in Aqueous Solution 下载免费PDF全文
Dr. Qian Wang Hong Yan Zhao Dr. Wai‐Lun Man Dr. William W. Y. Lam Dr. Kai‐Chung Lau Prof. Tai‐Chu Lau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10754-10758
The kinetics and mechanism of the reaction of SIV (SO32?+HSO3?) with a ruthenium(VI) nitrido complex, [(L)RuVI(N)(OH2)]+ (RuVIN, L=N,N′‐bis(salicylidene)‐o‐cyclohexyldiamine dianion), in aqueous acidic solutions are reported. The kinetic results are consistent with parallel pathways involving oxidation of HSO3? and SO32? by RuVIN. A deuterium isotope effect of 4.7 is observed in the HSO3? pathway. Based on experimental results and DFT calculations the proposed mechanism involves concerted N?S bond formation (partial N‐atom transfer) between RuVIN and HSO3? and H+ transfer from HSO3? to a H2O molecule. 相似文献
996.
Robert G. W. Anderson 《Ambix》2015,62(4):333-344
Following colonisation of South America by the Spanish, many new naturally occurring substances were sent to Europe. One of these was the silvery, unreactive metal, platinum, discovered in New Grenada in the mid-eighteenth century. It was often found in granular form, associated with gold, and the challenge to chemists was to refine it, produce it as wire or sheet, and determine its chemical properties. This interested the professor of chemistry at the University of Edinburgh, Joseph Black, who was able to obtain samples from London-based Spanish contacts, particularly Ignacio Luzuriaga. This paper examines how Black transmitted his knowledge of the metal to large numbers of students attending his annual course. 相似文献
997.
Suppressing the environmental dependence of the open‐circuit voltage in inverted polymer solar cells through a radical polymer anodic modifier 下载免费PDF全文
Lizbeth Rostro Lucio Galicia Bryan W. Boudouris 《Journal of Polymer Science.Polymer Physics》2015,53(5):311-316
Developing stable, readily‐synthesized, and solution‐processable transparent conducting polymers for interfacial modifying layers in organic photovoltaic (OPV) devices has become of great importance. Here, the radical polymer, poly(2,2,6,6‐tetramethylpiperidinyloxy methacrylate (PTMA), is shown to not affect the absorption of the well‐studied poly(3‐hexylthiophene) (P3HT) and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) active layer when incorporated into inverted OPV devices, as it is highly transparent in the visible spectrum due to the non‐conjugated nature of the PTMA backbone. The inclusion of this radical polymer as an anode‐modifying layer enhanced the open‐circuit voltage and short‐circuit current density values over devices that did not contain an anodic modifier. Importantly, devices fabricated with the PTMA interlayer had performance metrics that were time‐independent over the entire course of multiples days of testing after exposing the OPV devices to ambient conditions. Furthermore, these high performance values were independent of the metal used as the top electrode contact in the inverted OPV devices. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 311–316 相似文献
998.
Dr. Joice Thomas Dr. Liliana Dobrzańska Prof. Luc Van Meervelt Prof. Mario Alfredo Quevedo Prof. Krzysztof Woźniak Marcin Stachowicz Prof. Mario Smet Prof. Wouter Maes Prof. Wim Dehaen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):979-987
A synthetic route towards homodiselenacalix[4]arene macrocycles is presented, based on the dynamic covalent chemistry of diselenides. The calixarene inner rim is decorated with either alkoxy or tert‐butyl ester groups. Single‐crystal X‐ray analysis of two THF solvates with methoxy and ethoxy substituents reveals the high similarity of their molecular structures and alterations on the supramolecular level. In both crystal structures, solvent channels are present and differ in both shape and capacity. Furthermore, the methoxy‐substituted macrocycle undergoes a single‐crystal‐to‐single‐crystal transformation during which the molecular structure changes its conformation from 1,3‐alternate (loaded with THF/water) to 1,2‐alternate (apohost form). Molecular modelling techniques were applied to explore the conformational and energetic behaviour of the macrocycles. 相似文献
999.
Chae Bin Kim Dustin W. Janes Dana L. McGuffin Christopher J. Ellison 《Journal of Polymer Science.Polymer Physics》2014,52(18):1195-1202
The Marangoni effect describes how fluid flows in response to gradients in surface energy. This phenomenon could be broadly harnessed to pattern the surface topography of polymer films if generalizable techniques for programming surface energy gradients existed. Here, a near UV–visible light (NUV–vis) photosensitizer, 9,10‐dibromo‐anthracene (DBA), was doped into thin films of a model polymer, poly(isobutyl methacrylate). After exposure to light through a photomask and heating above the glass transition, thermolysis of photo‐oxidized DBA and grafting to the polymer promoted flow of the film material into the exposed regions. This mechanism did not significantly alter the molecular weight of PiBMA or the film's glass transition temperature, but resulted in an increase in film surface energy as indicated by a decrease in water contact angle. Film height variations of 580 nm were produced using a mask with 12.5 μm features; a mask with 800 nm features was also employed to generate topographic features of corresponding width without expensive contacting equipment. Due to the broad absorbance spectra of DBA, highly accessible and/or unconventional light sources may be employed in this process; this advantage was demonstrated by patterning with sunlight. The nonspecific radical‐mediated nature of the DBA grafting reaction makes this a promising approach for many classes of polymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1195–1202 相似文献
1000.