INTERNATIONAL SCHOOL OF PHYSICS AND CHEMISTRY OF THE ACTINIDES
Actinides -- the radioactive chemical elements that follow actinium in the Periodic Table -- form the backbone of nuclear fission technologies for electricity generation and have significant applications in other strategic fields, including human health, metrology, and space exploration.
As the atomic number increases from 90 to 103 in this series, additional electrons enter the highly anisotropic 5f shell. This shell is characterized by a radial wavefunction that extends relatively far from the nucleus, allowing 5f electrons to either form band states or retain a localized character.
The resulting properties are intricate. On one hand, strong intra-atomic electron correlations arise because the large nuclear charge pulls electrons into close proximity, favouring the formation of magnetic moments. On the other hand, quantum fluctuations of electronic and magnetic degrees of freedom can be so intense that they suppress magnetism, giving rise to emergent properties and novel classes of material behaviour near points of instability.
Additional sources of complexity include the hybridization between 5f and conduction-electron states, which can lead to a range of phenomena—from unconventional superconductivity to topologically protected states—and the interplay between spin and unquenched orbital degrees of freedom, which may result in exotic phase transitions driven by hidden multipolar order parameters.
Besides fundamental science interests, achieving a deep understanding of actinides is vital to ensuring a safe deployment of civil nuclear technologies. For instance, bringing the actinide theory to a “material-by-design” level is essential for reliably predicting the behaviour of nuclear waste-forms at very long term.
The School is intended to educate graduate students and early-career scientists in the physics and chemistry of actinides and their compounds, while fostering interactions among students, research centres, and university groups. It brings together leading experimental and theoretical experts to deliver advanced lectures and facilitate scientific discussions on the theory, simulation, and experimental investigation of the electronic and structural properties of actinide materials.
The program offers a comprehensive overview of the field, covering both foundational principles and the latest developments in theoretical and experimental approaches. Particular emphasis will be placed on critically examining the open questions and challenges that currently engage the scientific community. By assembling participants from diverse research backgrounds, the School also aims to promote the cross-fertilization of ideas, encouraging interdisciplinary dialogue and collaboration that could drive progress in this complex and rapidly evolving area of science.