Paul Niggli (26 June 1888 – 13 January 1953) was a

Swiss Swiss may refer to: * the adjectival form of Switzerland * Swiss people Places * Swiss, Missouri * Swiss, North Carolina *Swiss, West Virginia * Swiss, Wisconsin Other uses *Swiss-system tournament, in various games and sports *Swiss Internation ...

mineralogist Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proces ...

, and

petrologist Petrology () is the branch of geology that studies rocks and the conditions under which they form. Petrology has three subdivisions: igneous, metamorphic, and sedimentary petrology. Igneous and metamorphic petrology are commonly taught together ...

who was a leader in the field of

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

Education and career

Niggli was born in

Zofingen Zofingen (french: Zofingue) is a city in the canton of Aargau in Switzerland. It is the capital of the district of Zofingen. Zofingen is a walled city and home of an ancient monastic settlement. History In ancient times Zofingen was a settleme ...

and studied at the Swiss Federal Institute of Technology (ETH) in Zurich and the

University of Zurich The University of Zürich (UZH, german: Universität Zürich) is a public research university located in the city of Zürich, Switzerland. It is the largest university in Switzerland, with its 28,000 enrolled students. It was founded in 1833 f ...

, where he obtained a doctorate. His 1919 book, ''Geometrische Kristallographie des Diskontinuums'', played a seminal role in the refinement of

space group In mathematics, physics and chemistry, a space group is the symmetry group of an object in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of an object that leave it unchan ...

theory. In this book, Niggli demonstrated that although X-ray reflection conditions do not always uniquely determine the

to which a crystal belongs, they do reveal a small number of possible space groups to which it could belong. Niggli used morphological methods to account for internal structure and, in his 1928 ''Kristallographische und Strukturtheoretische Grundbegriffe,'' he took up what is essentially the reverse process, the task of establishing the connection between space lattices and external crystal morphology. The great aim of his life was to integrate the whole field of

Earth science Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres ...

s. In 1920, Niggli became the lead scientist at the ETH's ''Institut für Mineralogie und Petrographie'', where he brought his systematic approach to the study of crystal morphologies using

X-ray diffraction X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

. In 1935, Niggli and his doctoral student Werner Nowacki (1909–1988) determined the 73 three-dimensional arithmetic crystal classes ( symmorphic space groups). Niggli retired from the Institute in 1949. He was also professor of mineralogy at the ETH Zurich and at the University of Zurich. Niggli succeeded Paul Heinrich von Groth (1843–1927) as editor of '' Zeitschrift für Kristallographie''.

Honors and awards

In 1948, Niggli was awarded the

Roebling Medal The Roebling Medal is the highest award of the Mineralogical Society of America for scientific eminence as represented primarily by scientific publication of outstanding original research in mineralogy. The award is named for Colonel Washington ...

of the

Mineralogical Society of America The Mineralogical Society of America (MSA) is a scientific membership organization. MSA was founded in 1919 for the advancement of mineralogy, crystallography, geochemistry, and petrology, and promotion of their uses in other sciences, industry, ...

. Since 1988 th
Paul Niggli Foundation
awards medals to outstanding Swiss mineral scientists below the age of 35 with a strong perspective for an academic career.

Dorsum Niggli Dorsum Niggli is a wrinkle ridge at in Oceanus Procellarum on the Moon. It is 50 km long and was named after Paul Niggli Paul Niggli (26 June 1888 – 13 January 1953) was a Swiss crystallographer, mineralogist, and petrologist who was a lea ...

on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

was named after him.

Personal life

Niggli married Hedwig Dübendorfer (later Hedwig Niggli) in 1915. He had two children with her, Ernst Niggli and Hedi Fritz-Niggli.

Bibliography

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References

1888 births 1953 deaths Petrologists Swiss mineralogists ETH Zurich faculty ETH Zurich alumni People from Zofingen University of Tübingen faculty Leipzig University faculty University of Zurich alumni University of Zurich faculty Crystallographers {{geologist-stub