Annelore Köster-Pflugmacher

Annelore Köster-Pflugmacher (1919-2002): luminary of inorganic chemistry

Boron, germanium and the halogens: these elements were the focus of research by Annelore Köster-Pflugmacher. As a chemistry professor at RWTH Aachen University, she also taught extensively.

Annelore Köster-Pflugmacher (née Trapp) was born on March 19, 1919 in Königsberg in East Prussia (now Kaliningrad in Russian). After graduating from high school, she studied chemistry at the Albertus University in Königsberg. She completed her dissertation on silicon iodides with Robert Schwarz (1887-1963) at the Institute for Inorganic Chemistry there. On November 21, 1942, she was awarded a doctorate in natural sciences.

During her studies she met Dieter Pflugmacher, whom she married in 1941. However, the Second World War quickly made her a widow. Her husband fell in July 1943.

From July 1942 to November 1944, Pflugmacher worked as a research assistant at the chemical institute of the University of Königsberg. Shortly before the invasion of Russian troops in 1945, she fled to the West. In Aachen, Pflugmacher finally found a new professional home. She followed her doctoral supervisor, who in 1948 accepted an offer at the Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen as full professor for inorganic chemistry and electrochemistry. In April 1950, Pflugmacher was given a permanent position as a research assistant at RWTH, where she submitted her habilitation thesis in 1953 under the title ?On the knowledge of bromine oxides?. In 1960 she was appointed to an unscheduled professorship and in 1961 was appointed Scientific Councilor at RWTH Aachen University. During this time she met the chemist Alfred Köster, whom she married in 1962. Two years later the couple moved to Langenfeld in the Rhineland.

In her research, Köster-Pflugmacher concentrated on the oxides of bromine and the halides of boron as well as the organometallic compounds of germanium. She mainly used X-ray fluorescence spectroscopy as an analytical method. At RWTH she also did an extensive teaching job, since chemical training for students of mechanical engineering and other subjects was part of her area of responsibility. In addition, she supervised the chemistry lectures for the higher teaching post. From 1961 on, Köster-Pflugmacher was also the editor of the German-language new editions of the textbook "Qualitative Schnellanalyse der Kationen und Anionen" by Gaston Charlot (1904-1994), the founder of modern analytical chemistry in France.

In March 1981 Köster-Pflugmacher retired. RWTH Aachen recognized her post-doctoral thesis in 2010 in the calendar ?100 Years of Women's Studies at RWTH?. Annelore Köster-Pflugmacher was 83 years old and lived in Langenfeld until her death. She died on August 12, 2002.


  • H. Werner: History of Inorganic Chemistry, Wiley & Sons, Weinheim, 2016, p. 158
  • Memory of RWTH Aachen University, Alma Mater Aquensis, special volume 1870-1995, p. 71

The texts published in this series do not claim to be scientific publication. Authors and other persons involved are not experts in the history of science. The purpose of the series is to introduce the mostly unknown chemists and to remind them of the well-known chemists. We encourage readers who want to know more to study scientific sources on the women presented. In some cases there are detailed chemical-historical studies.

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last modified: 06.09.2021 09:05 H from K.J.Schmitz