New algorithm finds the optimal bond breaking point for single molecules

August 1, 2017
In this potential-surface picture, the red curve is a reaction pathway. The pink points are the optimal BBPs, and the black points are the minima and transition states. Green lines are the BBP points for all possible Newton trajectories. Credit: AIP Publishing

Recent developments in atomic-force microscopy have enabled researchers to apply mechanical forces to individual molecules to induce chemical reactions.

A research team from Spain and Germany has now developed a first-of-its-kind algorithm that determines the minimal force it takes to reach the optimal bond breaking point (BBP) at the molecular level to mechanically induce a chemical . They report their findings this week in The Journal of Chemical Physics.

The algorithm can be applied to any molecule, including biological like proteins as well as inorganic molecules. Their research has implications for numerous applications, including molecular machines, mechanically resilient and self-healing polymers, stress-responsive materials and catalyst design. The algorithm can also be used to explore how external electric fields can catalyze and control .

When studying mechano-chemical processes, researchers look for the mechanical response of the reactant molecule's minimum-energy structure. As the external force increases, the minimum energy and transition state structures on the force-modified potential energy surface become identical and the structure where this occurs is the sought-after BBP.

Molecular configuration of the optimal BBP of the 1, 2-sigmatropic H-shift rearrangement of cyclopentadiene. The arrows correspond to the components of the gradient at this point. Credit: AIP Publishing

"Our work highlights that there exists another set of important points on the potential energy surface of a given system, namely the BBP, which needs to be taken into consideration for mechano-chemistry applications," said Wolfgang Quapp, a co-author of the paper who added that BBP is a new concept in mechano-chemistry.

The optimal BBPs of a potential energy surface are crucial, according to Quapp, because they provide information about the way in which tensile forces should be applied to trigger chemical transformations with the highest possible efficiency using the least amount of force.

The bond, bending and torsion of a molecule have varying stiffness. Therefore, determining the force-bearing scaffold of a molecule, to predict, for example, the point of bond rupture in an overstretched molecule, means that different directions of the external force should be tested.

"Our algorithm allows researchers to identify which part of a molecule is most susceptible to mechanical stress, and thus the algorithm is a significant step in the design of more efficient ways of harnessing mechanical to activate chemical reactions," Quapp said. "The importance of the optimal BBP resides in that it gives the optimal direction and magnitude of the pulling . This necessitates an algorithm to easily find these types of points."

The is based on Newton trajectories, which come from the mathematical method of calculating zeros of a function. In the case of BBPs, the Newton trajectories are located near the reaction path of the reaction under consideration.

Explore further: Chemists build new chemical structures on unreactive bonds

More information: "An algorithm to locate optimal bond breaking points on a potential energy surface for applications in mechanochemistry and catalysis," Journal of Chemical Physics (2017). DOI: 10.1063/1.4994925

Related Stories

Chemists build new chemical structures on unreactive bonds

July 28, 2017

Making complicated organic molecules is like solving a Rubik's cube. Organic chemists need to design sequences of reactions to carefully build up parts of a molecule, while maintaining the structure at other sites. Although ...

On-surface chemistry leads to novel products

September 13, 2016

On-surface chemical reactions can lead to novel chemical compounds not yet synthesized by solution chemistry. The first-step, second-step, and third-step products can be analyzed in detail using a high-resolution atomic force ...

Pushing a single-molecule switch

July 15, 2016

An international team of researchers from Donostia International Physics Center, Fritz-Haber Institute of the Max Planck Society, University of Liverpool, and the Polish Academy of Sciences has shown a new way to operate ...

Mechanics meets chemistry in new way to manipulate matter

March 21, 2007

The inventors of self-healing plastic have come up with another invention: a new way of doing chemistry. Researchers at the University of Illinois at Urbana-Champaign have found a novel way to manipulate matter and drive ...

With more light, chemistry speeds up

May 5, 2017

Light initiates many chemical reactions. Experiments at the aser Centre of the Institute of Physical Chemistry of the Polish Academy of Sciences and the University of Warsaw's Faculty of Physics have, for the first time, ...

Recommended for you

Physicists design $100 handheld muon detector

November 20, 2017

At any given moment, the Earth's atmosphere is showered with high-energy cosmic rays that have been blasted from supernovae and other astrophysical phenomena far beyond the Solar System. When cosmic rays collide with the ...

A curious quirk brings organic diode lasers one step closer

November 20, 2017

Since their invention in 1962, semiconductor diode lasers have revolutionized communications and made possible information storage and retrieval in CDs, DVDs and Blu-ray devices. These diode lasers use inorganic semiconductors ...

Carefully crafted light pulses control neuron activity

November 17, 2017

Specially tailored, ultrafast pulses of light can trigger neurons to fire and could one day help patients with light-sensitive circadian or mood problems, according to a new study in mice at the University of Illinois.

Strain-free epitaxy of germanium film on mica

November 17, 2017

Germanium, an elemental semiconductor, was the material of choice in the early history of electronic devices, before it was largely replaced by silicon. But due to its high charge carrier mobility—higher than silicon by ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.