Amazing stuff with potential!
"In what's being hailed as an important first for chemistry, an international team of scientists has developed a new technology that can selectively rearrange atomic bonds within a single molecule. The breakthrough allows for an unprecedented level of control over chemical bonds within these structures, and could open up some exciting possibilities in what's known as molecular machinery. ...
These so-called molecular machines were the focus of the 2016 Nobel Prize in Chemistry ... for the creation of a molecular car powered by molecular motors spinning at 12 million revolutions per second. We've also seen scientists create molecular pumps, tiny gear wheels and molecular submarines to target cancer cells, to list just a few examples. ...
The research focuses on molecules known as structural isomers, which have the same atomic composition but different arrangement of bonds between those atoms. By using the tip of a scanning probe microscope to apply different voltage pulses, the team showed that they could selectively rearrange the chemical bonds. A molecule with a 10-membered carbon ring in the middle was able to converted into a molecule with a four- and eight-member ring, for example, or a molecule with two six-member rings in the center. These reactions were also reversible ..."
These so-called molecular machines were the focus of the 2016 Nobel Prize in Chemistry ... for the creation of a molecular car powered by molecular motors spinning at 12 million revolutions per second. We've also seen scientists create molecular pumps, tiny gear wheels and molecular submarines to target cancer cells, to list just a few examples. ...
The research focuses on molecules known as structural isomers, which have the same atomic composition but different arrangement of bonds between those atoms. By using the tip of a scanning probe microscope to apply different voltage pulses, the team showed that they could selectively rearrange the chemical bonds. A molecule with a 10-membered carbon ring in the middle was able to converted into a molecule with a four- and eight-member ring, for example, or a molecule with two six-member rings in the center. These reactions were also reversible ..."
"... We were able to target specific chemical bonds in those molecules, breaking those bonds and forging new, different ones to switch back and forth at will among three different molecular structures. ...
We used a combined scanning tunneling and atomic force microscope working in ultrahigh vacuum and at a temperature of 5 Kelvin. ..."
We used a combined scanning tunneling and atomic force microscope working in ultrahigh vacuum and at a temperature of 5 Kelvin. ..."
From the abstract:
"Controlling selectivity of reactions is an ongoing quest in chemistry. In this work, we demonstrate reversible and selective bond formation and dissociation promoted by tip-induced reduction-oxidation reactions on a surface. Molecular rearrangements leading to different constitutional isomers are selected by the polarity and magnitude of applied voltage pulses from the tip of a combined scanning tunneling and atomic force microscope. Characterization of voltage dependence of the reactions and determination of reaction rates demonstrate selectivity in constitutional isomerization reactions and provide insight into the underlying mechanisms. With support of density functional theory calculations, we find that the energy landscape of the isomers in different charge states is important to rationalize the selectivity. Tip-induced selective single-molecule reactions increase our understanding of redox chemistry and could lead to novel molecular machines."
Selectivity in single-molecule reactions by tip-induced redox chemistry (no public access)
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