my.chemeurope.com
With an accout for my.chemeurope.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
The on‐surface Ullmann‐type chemical reaction synthesizes polymers by linking carbons of adjacent molecules on solid surfaces. Although an organometallic compound is recently identified as the reaction intermediate, little is known about the detailed structure of the bonded organometallic species and its influence on the molecule and the reaction. Herein atomic force microscopy at low temperature is used to study the reaction with 3,9‐diiododinaphtho[2,3‐b:2′,3′‐d]thiophene (I‐DNT‐VW), which is polymerized on Ag(111) in vacuum. Thermally sublimated I‐DNT‐VW picks up a Ag surface atom, forming a CAg bond at one end after removing an iodine. The CAg bond is usually short‐lived, and a CAgC organometallic bond immediately forms with an adjacent molecule. The existence of the bonded Ag atoms strongly affects the bending angle and adsorption height of the molecular unit. Density functional theory calculations reveal the bending mechanism, which reveals that charge from the terminus of the molecule is transferred via the Ag atom into the organometallic bond and strengths the local adsorption to the substrate. Such deformations vanish when the Ag atoms are removed by annealing and CC bonds are established.
High‐resolution atomic force microscopy with a functionalized CO tip allows us to observe inner structures of molecules. Here, a structural information of the organometallic bond formed on a Ag(111) surface is obtained at low temperature. The detailed behavior of the Ag atom to the molecular unit was in‐depth investigated.
| Authors: | Shigeki Kawai, Ali Sadeghi, Toshihiro Okamoto, Chikahiko Mitsui, Rémy Pawlak, Tobias Meier, Jun Takeya, Stefan Goedecker, Ernst Meyer | |
| Journal: | Small | |
| Year: | 2016 | |
| Pages: | n/a | |
| DOI: | 10.1002/smll.201601216 | |
| Publication date: | 17-Aug-2016 |
The unfolding landscape of the congenital myasthenic syndromes
Abstract Congenital myasthenic syndromes (CMS) are heterogeneous disorders in which the safety margin of neuromuscular transmission is impaired by one or more specific mechanisms. Since the advent of next‐generation sequencing methods, the discovery of novel CMS targets and phenotypes ha ... more
Passive transfer models of myasthenia gravis with muscle‐specific kinase antibodies
Abstract Myasthenia gravis (MG) with antibodies to muscle‐specific kinase (MuSK) is characterized by fluctuating fatigable weakness. In MuSK MG, involvement of bulbar muscles, neck, and shoulder and respiratory weakness are more prominent than in acetylcholine receptor (AChR) MG. MuSK au ... more
Abstract Because of the failure of many promising therapeutics identified in preclinical evaluation, funding sources have established guidelines for increased rigor in animal evaluations. The myasthenia gravis (MG) community of scientists has developed guidelines for preclinical assessme ... more
Smart skin made of recyclable materials may transform medicine and robotics
Smart skin that can respond to external stimuli could have important applications in medicine and robotics. Using only items found in a typical household, researchers have created multi-sensor artificial skin that's capable of sensing pressure, temperature, humidity, proximity, pH, and air ... more
How mercury contamination affects reptiles in the Amazon basin
Mercury contamination in water and on land is of worldwide concern due to its toxic effects on ecosystems and human health. Mercury toxicity is of particular concern to reptiles because they are currently experiencing population declines. Also, reptiles are ideal indicators of mercury conta ... more
Bioengineers Succeed in Producing Plastic Without the use of Fossil Fuels
A team of pioneering South Korean scientists have succeeded in producing the polymers used for everyday plastics through bioengineering, rather than through the use of fossil fuel based chemicals. This groundbreaking research, which may now allow for the production of environmentally consci ... more
Read what you need to know about our industry portal chemeurope.com.
© 1997-2021 LUMITOS AG, All rights reserved
