Actinide Bonding Analysis in Position Space

Actinides are a fascinating class of elements. They are difficult to work with in the laboratory, but they are also very challenging for the theoretician. The open f-shell sometimes necessitates the use of multi-reference calculations. They contribute many electrons, making the calculation more demanding. And lastly, relativistic effects become important. These problems certainly contribute to the situation in which far less is known and understood about actinide chemistry compared to e.g. the lanthanides. In this contribution, we use analysis methods that work in real space, i.e. on the electronic density. We present different tools and the application to the bonding in BTP complexes on actinides and lanthanides . BTP complexes have been investigated for numerous years now and it is still not entirely understood, why they bind actinides more strongly than lanthanides. The presented data is hopefully a step towards the solution of that problem.