Pre-1962

This extract from 50 Years of X-ray Diffraction, edited by P. P. Ewald and published in 1962, recounts the early development of crystallography in this region.

Switzerland

The development of diffraction methods in this country was shaped mainly by the prominent men in Zürich: P. Debye, P. Scherrer, and P. Niggli. They came to Zürich in 1920, the former two to the Physics Department, the latter to that of Mineralogy and Petrography of the E.T.H. In neither of these places did much interest evolve in crystal structure determination as such, although Niggli analysed tenorite, and under Scherrer the structures of ferroelectric crystals like Rochelle salt were investigated. In Niggli's institute the emphasis lay on the general laws of crystalline architecture in a rather abstract, geometrical and classifying sense; E. Brandenberger's important analysis of the laws of extinctions, and H. Heesch's extension of the theory of space groups to include anti-symmetry elements should, however, be mentioned.

Crystal structure analysis in the accepted sense was used on a large scale from 1930 onwards by the physico-chemist W. Feitknecht in Bern, initially in conjunction with W. Lotmar. Systematic chemical surveys of series of compounds, such as the basic salts of bivalent metals, double hydroxides, and hydroxy salts were carried through mainly using powder diagrams, and led to extensive series of papers; Lotmar later turned to high-polymer and protein diffraction. In the department of mineralogy of the same university, Bern, W. Nowacki has built up an active and well equipped centre of structure analysis. A great variety of crystals, ranging from minerals to sterines and other organic crystals of high molecular symmetry have been determined here. The principles of crystalline structure, and the statistics of the distribution of structures among the space groups have drawn the particular interest of Nowacki (for the latter see Donnay and Nowacki, Crystal Data, Memoir 60, Geological Soc. of America, 1954).

In the years 1932-38 (approximately) a very active school of X-ray optics flourished in Geneva under the physicist J. Weigle. In a number of papers Weigle and his co-workers tested the validity of the dynamical theory of X-ray diffraction, and also laid the foundations for the understanding of the moiré patterns which are very revealing in electron diffraction and microscopy. This school came to an end when Weigle turned his interest to genetics and settled in U.S.A.

A re-activation has taken place in the mineralogical institute in Zürich since the appointment of F. Laves as professor of crystallography; an interesting program of research into the relations of structural and physical properties is developing on a broad front. A. Niggli has further extended the mathematical theory of space groups.

Needless to say that in a highly industrialized country like Switzerland X-ray diffraction is being used in the chemical, metallurgical, electrical industries and in the special Laboratoire suisse des Recherches horlogères in Neuchâtel.

First published for the International Union of Crystallography 1962 by N.V.A. Oosthoek's Uitgeversmaatschappij, Utrecht, The Netherlands
Digitised 1999 for the IUCr XVIII Congress, Glasgow, Scotland
© 1962, 1999 International Union of Crystallography