Piet Hartman

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Piet Hartman (born April 11, 1922 ) is a Dutch crystallographer.

Career

Hartman studied chemistry at the University of Groningen and received his doctorate there in 1953 under the supervision of Pieter Terpstra. He then became a professor at the geological faculty in Leiden . After the merger of the geological faculties of Leiden and Utrecht, he became professor at the University of Utrecht in 1978 , where he remained until his emeritus in 1987. In 1981 he was elected a member of the Leopoldina .

Hartman-Perdok theory

Hartman studied the relationship between crystal structure and crystal morphology . The first theories on this go back to Auguste Bravais . According to Bravais, those surfaces form in the crystal that have the greatest density of lattice points. According to this, the crystal morphology only depends on the lattice symmetry ( Bravais lattice ) and the lattice parameters . Later theories indicated that screw axes and glide mirror planes also have an influence, i.e. the entire symmetry of the space group .

Hartman and Perdok found that the crystal morphology depends on the intermolecular bonds between the crystal building blocks (molecules, ions). An unbroken chain of strong intermolecular bonds is known as a periodic bond chain and has the greatest rate of growth. Crystal directions that grow fastest grow out of the crystal and thus have disappeared. Almost all of today's programs for predicting crystal morphology are based on the Hartman-Perdok theory (periodic bond chain theory) or modifications thereof.

Fonts

  • P. Hartman, WG Perdok: On the relations between structure and morphology of crystals. I . In: Acta Crystallographica . tape 8 , no. 1 , 1955, pp. 49-52 , doi : 10.1107 / S0365110X55000121 .
  • P. Hartman, WG Perdok: On the relations between structure and morphology of crystals. II . In: Acta Crystallographica . tape 8 , no. 9 , 1955, pp. 521-524 , doi : 10.1107 / S0365110X55001679 .
  • P. Hartman, WG Perdok: On the relations between structure and morphology of crystals. III . In: Acta Crystallographica . tape 8 , no. 9 , 1955, pp. 525-529 , doi : 10.1107 / S0365110X55001680 .

Web links

Individual evidence

  1. ^ Member entry by Piet Hartman at the German Academy of Natural Scientists Leopoldina , accessed on July 11, 2016.
personal data
SURNAME Hartman, Piet
BRIEF DESCRIPTION Dutch crystallographer
DATE OF BIRTH April 11, 1922