Diamond anvil cell

A diamond anvil cell ( DAC, diamond anvil cell of English ), also diamond anvil press is a device for compression of small samples at very high pressure. It is used in scientific experiments. The pressures that are achieved are in Gigapascal area, which corresponds to 10,000 times Earth's air pressure. At these pressures, e.g., is Graphite transformed into diamond and created minerals with crystal structures that do not occur on the earth's surface.

Construction

A diamond anvil cell DAC consists of two opposing cut diamonds ( diamonds ), between the Kaletten ( tips), the material sample is located. The hydraulic pressure is reached by compression of the apparatus sealed with the aid of sample sets, being used as a transmission medium, argon, xenon, hydrogen, helium, liquid paraffin or a mixture of methanol and ethanol.

Operation

The size of the pressure reached in the material sample is obtained from the comparison with a reference material having a known behavior under pressure, is determined.

The sample or the behavior can be observed and measured by the diamond therethrough, said X-ray radiation, visible light and other electromagnetic waves may be used.

The attachment of electrodes to the sample material allows measurements as well as heating the sample up to several thousand degrees. Temperatures up to 7000 degrees in the sample can be achieved using laser -induced heating.

Diamentstempelzellen in the service of Geology

Diamentstempelzellen are used by geochemists and geophysicists within the mineralogy as part of Geomaterialforschung for laboratory experiments. These experiments are designed to answer the question of which materials are formed under extremely high pressure and temperature conditions that prevail within the earth and what physical and chemical properties they have. Special Hochleistungsdiamentstempelzellen where the highest pressures are concentrated on a surface that is less than one square millimeter, the pressure supply in the cell up to a few million atmospheres and by means of laser heating temperatures of several thousand degrees. Since the samples are no longer visible to the naked eye, microscopic techniques, X-ray spectroscopy and laser spectroscopy are used to Analsyse the results. Here, the interest of the study of metamorphic rock formation extends to the fundamental question of how the original magma of the earth separated by lowering the heavier molten metal from the less dense silicate environment into a metallic core and a liquid, viscous silicate melt. Interest is the possibility of the element distribution between silicate and metal melts, its viscosity and the heat transfer in minerals and melting. These questions are important for understanding the Erddynamik of fundamental importance. Experiments with Diamentstempelzellen also be used to check ab-initio molecular dynamics simulations.