Diatomic molecules are ubiquitous in our environment, as in the air we breathe, but if we increase the pressure by gradually bringing them closer together, until when can we still speak of differentiated molecules?
Modelling and measuring with an accuracy close to a thousandth of an Angstrom the change with pressure of the intramolecular distance of the halogens (I2, Br2), the authors showed the formation of bonds between molecules which affect the state of the molecule itself at pressures much lower than the metallisation or dissociation pressures of diatomic molecules. This phenomenon could be more general and have implications in areas such as the structure of giant planets, composed essentially of another diatomic molecule at high pressure: hydrogen.
"Halogen molecular modifications at high pressure: the case of iodine" in the journal Physical Chemistry Chemical Physics. This paper was selected as "Hot topic 2021" by the editor and is distributed free of charge.