Obituary for Prof. Peter H. Dederichs (1938–2026)
The Peter Grünberg Institute (PGI) mourns the loss of its long-standing colleague Prof. Dr Peter Heinz Dederichs, who passed away on 1 August 2026 at the age of 87. With his passing, Forschungszentrum Jülich has lost an outstanding scientist who played a decisive role in shaping theoretical solid-state physics at Jülich over many decades.
Peter H. Dederichs studied physics at RWTH Aachen University, where he obtained his doctorate in 1965 and completed his habilitation in 1971. He began conducting research at Forschungszentrum Jülich in 1971 – and remained closely associated with the centre and the scientific community even after his retirement in 2004. He was one of the pioneers of solid-state physics in Germany and was internationally recognised as a leading expert on its theoretical foundations.
As early as the late 1970s, Dederichs recognised the importance of new theoretical and computer-aided methods for a quantitative understanding of the properties of solids and immediately focused his research in this direction. Together with colleagues at the predecessor institute of what is now the PGI – the Institute for Solid State Research (IFF) – he developed innovative ab initio methods for calculating the electronic structure of solids. Such approaches are now indispensable to modern materials science and nanoscience. By applying these methods, he made important contributions to the fields of nanomagnetism and spintronics. In recognition of his scientific work in theoretical solid-state physics and the ab initio description of the electronic structure of materials, he was awarded the Ernst Mach Honorary Medal for Merit in the Physical Sciences by the Czech Academy of Sciences in 2006.
Furthermore, Peter Dederichs left his mark on research at Jülich far beyond his own scientific work. He possessed an excellent instinct for scientific networking and established successful collaborations in Europe and Japan. He placed particular emphasis on fostering collaboration within the PGI and Forschungszentrum Jülich. As a long-standing group leader at Forschungszentrum Jülich and a professor at RWTH Aachen University, he had been living out the close connection between the two institutions long before this collaboration was formally established. Even before the fall of the Berlin Wall, Dederichs maintained excellent contacts with colleagues in what was then the GDR. During the years of German reunification, he became an important and reliable point of contact for numerous young scientists. Long after his retirement, he remained exceptionally active in research. From 2004 to 2011, he was chair of the European network Psi-k, which brings together researchers in the field of electronic structure and ab initio materials modelling across Europe. Dederichs had already played a key role in its establishment and development during the 1980s and 1990s.
In 2012, Peter Dederichs received a special honour in recognition of his lifetime scientific achievements when he was awarded a Helmholtz Professorship. At the time, he was only the third scientist at Jülich to receive this distinction – following Nobel laureate Peter Grünberg and Siegfried Mantl.
His colleagues will remember Peter Dederichs not merely as an eminent scientist. He was a warm and amiable person, as well as an inspiring and dedicated mentor to PhD students and postdocs. He served the Forschungszentrum for many decades in a wide variety of roles and remained closely connected to it even after that. Through his scientific work, his experience and his personal commitment, he had a lasting impact on the research environment in Jülich.
We shall honour the memory of Peter H. Dederichs.