Chemistry is based on the idea that atoms They are linked by bonds whose cohesion determines the properties of the materials that surround us. Therefore, to design new materials and chemical compounds, it is necessary to know if the atoms can be held together at certain distances.
In a recent study, published in Angewandte Chemie, a research team from the Complutense University of Madrid (UCM) and the University of Oviedo (UNIOVI) has proposed a model that allows knowing the minimum and maximum limit necessary for the Chemical bond between a pair of atoms is maintained without altering its composition.
The application of these results will save many tests in the synthesis of new compounds in laboratories
Álvaro Lobato, researcher at the Complutense University of Madrid
This work opens a new avenue for the study of chemical bonding while providing synthetic rules for the search for new compounds that facilitate our life, such as new materials or drugs.
“The application of these results will save many tests in the synthesis of new compounds in laboratories, knowing in advance the limits of stability of materials when they are exposed to extreme stress ”, he highlights Álvaro Lobato, the researcher from the Department of Physical Chemistry of the UCM and one of the authors of the study.
Although chemical bonds are present in research and studies on the properties of materials, there is no scientific consensus on the concept of bonding.
According Jose Manuel Recio, Professor of Physical and Analytical Chemistry at UNIOVI and another of the authors, “The importance of this finding resides in its general utility for all chemists because the bond distance is an everyday parameter present in any of the branches of chemistry.”
Like a ‘dock’
The bonds between atoms act as a spring in which, depending on the molecule or solid in which this link is located, it can be compressed or stretched by varying its size, which will lead to shorter or longer link distances.
“Like springs, links can break when we stretch or compress them too much. To date, no one had been able to find a simple recipe with which to calculate how small or large these link distances could be before breaking, ”says Lobato.
The stretching or compression force that a bond undergoes is measured through the so-called potential energy curves, which have the same shape for any type of link. Using this universality of potential energy curves, the authors have established a relationship between distance and the maximum force that a link can withstand without breaking.
To date, no one had managed to find a simple recipe with which to calculate how small or large these bond distances could be before breaking.
To validate their model, they analyzed more than 1000 bond distances in molecules and solids, which include very important bonds such as carbon-carbon or hydrogen bonds.
The results obtained in this research open a new field of analysis of the chemical bond, explaining, among other things, why the carbon-carbon bond lengths in the millions of organic compounds that we know today do not vary more than a few hundredths of a nanometer between them. .
Lobato et al. “Highs & Lows in bond lengths: Is there any limit?” Angewandte Chemie. 2021. DOI: 10.1002 / anie.202102967.
Rights: Creative Commons.