Physicists develop improved algorithms for simulating how complex molecules respond to excitation by photons

July 31, 2018, Springer

What makes it possible for our eyes to see? It stems from a reaction that occurs when photons come into contact with a protein in our eyes, called rhodopsin, which adsorbs the photons making up light.

In a paper published in EPJ B, Federica Agostini, University Paris-Sud, Orsay, France, and colleagues propose a refined approximation of the equation that describes the effect of this photo-excitation on the of molecules. Their findings also have implications for other molecules, such as azobenzene, a chemical used in dyes. The incoming triggers certain reactions, which can result, over time, in dramatic changes in the properties of the molecule itself. This study was included in a special anniversary issue of EPJ B in honour of Hardy Gross.

Biochemical molecules are so complex that it would require far too much computer power to realistically predict how their molecular structures come to fold in a particular way—and thus acquire their functionalities—after reactions sparked by photon impacts. Instead, physicists use simpler, approximate models to understand the effects of incoming photons on the microscopic components of .

Specifically, the authors model the impact of an incoming photon on electrons and nuclei as the electrons approach an excited state. They perform simulations taking into account the specific properties of the building blocks of the molecule, making the approximations slightly closer to the physical reality of this phenomenon than previous work.

To illustrate the effectiveness of their approach, the authors apply it to a simple example. They demonstrate that the are able to pass through the energy barriers separating stable states by means of a tunnelling process. Nuclei are also able to populate the after incoming photons excite electrons.

Explore further: Physicists demonstrate new method to make single photons

More information: Federica Agostini et al, Nuclear quantum effects in electronic (non)adiabatic dynamics, The European Physical Journal B (2018). DOI: 10.1140/epjb/e2018-90144-3

Related Stories

Physicists demonstrate new method to make single photons

July 23, 2018

Scientists need individual photons for quantum cryptography and quantum computers. Leiden physicists have now experimentally demonstrated a new production method. Publication in Physical Review Letters on July 23rd.

Controlling photons with a photon

June 28, 2018

Photons are considered to be ideal information carriers and expected to play important roles in quantum communication and information processing, where quantum mechanics allows for absolutely secure cryptographic key distribution ...

A quantum of light for materials science

December 1, 2015

Computer simulations that predict the light-induced change in the physical and chemical properties of complex systems, molecules, nanostructures and solids usually ignore the quantum nature of light. Scientists of the Max-Planck ...

NA64 hunts the mysterious dark photon

November 25, 2016

One of the biggest puzzles in physics is that eighty-five percent of the matter in our universe is "dark": it does not interact with the photons of the conventional electromagnetic force and is therefore invisible to our ...

An example of plasmons directly impacting molecules

May 10, 2018

A team of researchers from Japan, Korea and the U.S. has found a way to demonstrate an example of plasmons directly causing changes to a molecule. In their paper published in the journal Science, the group describes their ...

Recommended for you

Researchers succeed in imaging quantum events

August 20, 2018

Quantum technology is a growing field of physics and engineering which utilizes properties of quantum mechanics as a basis for advanced practical applications such as quantum computing, sensors, information, communication ...

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.