Obituary Prof. Jan Jadżyn

Prof. Jan Jadżyn, PhD, DSc, was born on the January 13, 1943 in Skorodyńce (now in Ukraine) and died April 5, 2022 at his home in Skórzewo, Poland. He studied at the Faculty of Mathematics, Physics and Chemistry of the Adam Mickiewicz University in Poznan, Poland, and received the master’s degree in 1965. In 1971 prof. Jadżyn defended his doctoral dissertation, in which he analysed the influence of electric permittivity on the hydrogen bond polarity in organic complexes. 1974 he was awarded the postdoctoral degree (habilitation) based on the dissertation „Study of solvation of dipolar molecules in neutral solvents”. Later, in 1986, prof. Jadżyn obtained a professorship in physical sciences. His professional scientific career started 56 years ago in the Department of Dielectrics of the Institute of Physics of the Polish Academy of Sciences in Poznań, when he was appointed to a position as assistant in the Liquid Dielectrics Group. Since 1975 Jan Jadżyn was linked to the Institute of Molecular Physics of the Polish Academy of Sciences in Poznań where he founded the dielectric laboratory and for 26 years (1988–2014) served as Head of the Department of Dielectrics. His research topics were mainly concentrated on the dielectric properties of liquids with hydrogen bonds and mesogenic molecular systems. He was especially interested in the study of properties of extremely diluted solutions of dipolar molecules and pretransitional effects in liquid crystals. For many terms of office Jan was a valued member of the Scientific Council of the Institute of Molecular Physics. He was an active member of the International Liquid Crystal Society (ILCS) and one of the founding members of the very active Polish Liquid Crystal Society (PLCS) and later one of its Honorary Members. Furthermore, Jan was a member of the scientific committees of several European Conferences on Liquid Crystals (ECLC) over the years. During his career Prof Jadżyn was a visitor to many universities and research institutions, among them the Universities of Nancy and of Lille in France, the Catholic University of Leuven in Belgium, the University of Münster in Germany and the Institute of Experimental Physics in Koszyce in Slovakia. In particular, Jan valued the collaboration with scientists of the Institute of Chemistry at the Military University of Technology in Warsaw. Prof Jadżyn was a well-respected and valued teacher by generations of young physicists and a long-time higher education lecturer at the Poznań University of Technology. During his career, Professor Jan Jadżyn has published more than 240 papers, mostly on dielectric studies, in different highly regarded journals of international impact. Selected publications of Professor Jan Jadżyn are given below: * K. Prałat, J. Jadżyn, S. Balanicka, Dielectric properties and molecular structure of amide solutions. 1. N-methylacetamide in carbon tetrachloride, J. Phys. Chem. 87 (1983) 1385–1390 * J. Jadżyn, M. Stockhausen, B. Żywucki. Structure of hydrogen-bonded sym-dialkylureas in non-polar organic media, J. Phys. Chem. 91 (1987) 754–757 * J. Jadżyn, G. Czechowski, R. Douali, C. Legrand, On the molecular interpretation of the dielectric relaxation of nematic liquid crystals. Liquid Crystals 26 (1999) 1591–1597 * P. Kędziora, J. Jadżyn, L. Hellemans, Dynamics of the nonlinear dielectric properties of a nematogenic compound dissolved in a non-polar medium, Phys. Rev. E 66 (2002) 021709 * J. Świergiel, L. Bouteiller, J. Jadżyn, Concentration evolution of the dielectric response of hydrogen-bonded supramolecular polymers formed by dialkylurea in nonpolar medium, Macromolecules 47 (2014) 2464–2470