Chemistry is the science about matter - its stability, reactivity, transformations, interactions with external electromagnetic fields and radiation. However, we are mostly familiar with chemistry under conditions that can be realized on Earth. Under other conditions, chemistry changes in ways that cannot easily be predicted or understood from our experience with Earth-like chemistry.

For example, in the atmospheres of certain stellar objects such as rotating white dwarfs and neutron stars, extreme magnetic fields exist that cannot be generated on Earth. Knowledge about chemistry under such conditions can only be gained by performing advanced quantum-mechanical simulations, solving the Schrödinger equation for the electrons and nuclei that constitute matter.

Such calculations reveal an exotic, unfamiliar chemistry - molecules become squeezed and twisted, behaving in unexpected, fascinating ways. Even chemical bonding is affected - in a strong magnetic field, atoms are bound to one another by the rotation of the electrons, giving rise to molecules that do not exist on Earth.

In the project Molecules in Extreme Environments, we aim not only to understand chemistry under extreme conditions such as strong magnetic fields, extreme pressure, and intense laser pulses - we also aim to guide experimental work. Our work on magnetic bonding has already triggered experimental investigations on impurities in semiconductors, where similar effects may occur and lead to the design of materials with new properties. Likewise, a recent collaboration with astrophysicists aims to detect molecules in the atmospheres of white dwarfs, guided by quantum-mechanical simulations.