Werner Heinz Baur (1931–2025)

It is with great sadness that I share the news that Werner Heinz Baur passed away peacefully at home on Saturday, November 1, 2025, at the age of 94 with his wife, Renate, at his side. Werner was a pioneer in crystal chemistry with a focus on chemical bonding. He published more than 180 papers on this topic in scientific journals between 1956 and 2023 that have been cited nearly 9000 times. Just his publication on the geometry of polyhedral distortions in phosphate groups has been cited more than 1200 times. Later, his research focused primarily on zeolite-type structures. In this field, he published eight books with a total of more than 3000 pages in the Landolt-Börnstein series of the Springer Verlag. From 1989 to 2019 he was a member of the Structure Commission of the International Zeolite Association and subsequently became an Honorary Life member.

His deep interest in historical aspects is documented in his article “One hundred years of inorganic crystal chemistry – a personal view” published in Crystallography Reviews in 2014 (Baur, 2014). The article describes the scientific achievements of crystal chemistry from the fifth century to the present day. Among others, it covers Kepler's idea of crystals being composed of ordered particles in 1611, the findings of the Braggs (father and son) concerning crystal structures in the early 20th century, and Pauling’s famous rules from 1928/1929 concerning the bonding in ionic crystals, which Werner Baur himself extended in 1970 by two additional rules on distances in coordination polyhedra.

The mineral wernerbaurite, an ammonium-bearing decavanadate with chemical composition (NH₄)₂[Ca₂(H₂O)₁₄](H₂O)₂V₁₀O₂₈ was named after him in 2013. The mineral was found in the St Jude mine in Colorado, USA, and described by Tony Kampf and coauthors in the Canadian Mineralogist, who dedicated it to Werner’s “long, productive and distinguished career in mineralogical crystallography” (Kampf et al., 2013).

Werner was born in Warsaw in 1931. He moved to Göttingen at a young age where he went to school and studied mineralogy and crystallography at the university. He obtained his PhD in 1956 at the Georg-August-Universität in Göttingen with a dissertation on rutile-type crystal structures. In 1957 he was a scientific assistant at the Institute of Mineralogy at the University of Bern, Switzerland. He returned to Göttingen in 1961, where he was appointed as a Privatdozent. A year later, he married Renate, who accompanied him until the end of his life. In 1962 he went to Brookhaven National Laboratory where he was Associate Chemist in the Department of Chemistry. In 1963, he became an Assistant Professor at the Department of Earth and Planetary Sciences at the University of Pittsburgh, Pennsylvania. From 1968 to 1986 he was a Professor of Geological Sciences at the University of Illinois, Chicago, and from 1986 to 1996 Professor of Crystallography and Mineralogy at the University of Frankfurt, Germany. He then returned to the United States as a Senior Scientist at the University of Chicago between 1997 and 2003, and a Visiting Scholar at Northwestern University, Evanston, Illinois, from 2004 to 2010. He stayed scientifically active until he passed away. We will always keep him in our memories.