Gennes, Pierre-Gilles de, << zhehn, pyair zheel duh >> (1932-2007), a French theoretical physicist, improved the understanding of the behavior of substances consisting of large molecules. He won the 1991 Nobel Prize for physics for his work. His findings threw light on how molecules become more orderly or more disorderly under the influence of such things as temperature, and electric and magnetic fields.
The materials de Gennes worked on include polymers, such as plastics, and liquid crystals, which are most familiar from the displays in calculators and digital watches. See Liquid crystal ; Polymer .
De Gennes studied a wide variety of problems in the field of solid-state physics, also called condensed-matter physics, the physics of solids and liquids. He worked on superconductors–materials that lose all electrical resistance when they are cooled below a certain temperature. Later he studied liquid crystals, which are liquids and therefore able to flow, but whose molecules have a certain degree of order. In certain liquid crystals, the molecules can be lined up by applying electric fields, affecting light passing through them. This principle is the basis of the liquid-crystal display (LCD).
Other problems that de Gennes worked on include wetting, the interaction between a liquid and a solid surface that causes the liquid to spread out on the surface. Many industrial processes are made more efficient if a liquid is made to wet a solid more effectively. Another problem that arises at the point of contact between different materials and that de Gennes studied is that of adhesion–the bonding of different substances.
Pierre-Gilles de Gennes was born in Paris on Oct. 24, 1932, and took his first degree at the Ecole Normale Superieure in 1955. He worked at the French government’s nuclear energy research center at Saclay for several years, obtaining his Ph.D. in 1957. After working at the University of California, at Berkeley in the United States, and doing his national service in the French navy, he taught at the College de France in Paris and at the University of Paris. In 1976, de Gennes became director of the College of Industrial Physics and Chemistry, also in Paris. De Gennes died on May 18, 2007.
