Obituary for Prof. Arnold


Obituary for Prof. Arnold

Professor Arnold giving a speech Copyright: crystallography

The Department of Geosciences and Geography mourns the death of Prof. Dr. rer. nat. Heinrich Arnold.

Prof. Arnold was born on October 21, 1930 in Budapest / Hungary and studied at the University of Marburg, where he completed his studies in 1958 as a graduate physicist with a thesis on "The Crystallization of Terylene in the Small Angle Diagram" with Prof. Dr. Carl Hermann graduated. He then worked at the Max Planck Institute for Silicate Research with Prof. Dr. Heinz Jagodzinski. He received his doctorate in 1964 from the University of Würzburg with a thesis on “Structure and disorder in the α-ß conversion of quartz”. From 1964 he worked at the newly founded Institute for Crystallography at RWTH Aachen University with Prof. Dr. Theo Hahn, initially as a research assistant and later as a senior engineer. After a time as a Postdoctoral Fellow in 1967/68 at the Georgia Institute of Technology in Atlanta / USA, he completed his habilitation in 1976 at RWTH Aachen University with a thesis on "Displacement phase transformation, lattice dynamics and X-ray diffraction" and was appointed lecturer in the field of crystallography in 1979. From 1982 until his retirement in 1995 he worked as an APL professor at the Institute for Crystallography at RWTH Aachen University and from October 1st, 1993 to September 30th, 1995 he was also the spokesperson for the specialist group.

Prof. Arnold was a staunch scientist and university professor. He played a key role in setting up the Institute for Crystallography at RWTH Aachen University, which was newly founded in 1963, in particular in setting up the X-ray laboratories and the associated courses, which were also attended by numerous external participants. Due to his interest in scattering methods with X-ray and neutron beams, he built a high-temperature powder diffractometer for synchrotron radiation at DESY in Hamburg and was involved in setting up the UNIDAS neutron 3-axis spectrometer at FZ Jülich.

Prof. Arnold's scientific interest was primarily in the structural phase transitions. Particularly noteworthy are his work on the high-low conversion of quartz, including his dissertation and habilitation thesis.
Due to his expertise in the field of symmetry, he has been a major contributor to the new edition of the International Tables for Crystallography together with Prof. Theo Hahn on behalf of the International Union of Crystallography.
With his death on October 9, 2020, RWTH lost a highly valued colleague, active scientist and popular teacher. Our deepest condolences go to his family. We will always keep an honorable memory of Prof. Arnold.