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A diamond anvil cell (DAC) is a device used in scientific experiments. It allows compressing a small (sub-millimeter-sized) piece of material to extreme pressures, which can exceed 600 gigapascals (6,000,000 bars / 6 million atmospheres).〔(Improved diamond anvil cell allows higher pressures ). ''Physics World'' November 2012〕 The device has been used to recreate the pressure existing deep inside planets, creating materials and phases not observed under normal conditions. Notable examples include the non-molecular ice X, polymeric nitrogen and metallic xenon (an inert gas at lower pressures). A DAC consists of two opposing diamonds with a sample compressed between the culets (tips). Pressure may be monitored using a reference material whose behavior under pressure is known. Common pressure standards include ruby fluorescence, and various structurally simple metals, such as copper or platinum. The uniaxial pressure supplied by the DAC may be transformed into uniform hydrostatic pressure using a pressure transmitting medium, such as argon, xenon, hydrogen, helium, paraffin oil or a mixture of methanol and ethanol. The pressure-transmitting medium is enclosed by a gasket and the two diamond anvils. The sample can be viewed through the diamonds and illuminated by X-rays and visible light. In this way, X-ray diffraction and fluorescence; optical absorption and photoluminescence; Mössbauer, Raman and Brillouin scattering; positron annihilation and other signals can be measured from materials under high pressure. Magnetic and microwave fields can be applied externally to the cell allowing nuclear magnetic resonance, electron paramagnetic resonance and other magnetic measurements. Attaching electrodes to the sample allows electrical and magnetoelectrical measurements as well as heating up the sample to a few thousand degrees. Much higher temperatures (up to 7000 K) can be achieved with laser-induced heating, and cooling down to millikelvins has been demonstrated.〔 ==Principle== The operation of the diamond anvil cell relies on a simple principle: : where ''p'' is the pressure, ''F'' the applied force, and ''A'' the area. Therefore, high pressure can be achieved by applying a moderate force on a sample with a small area, rather than applying a large force on a large area. In order to minimize deformation and failure of the anvils that apply the force, they must be made from a very hard and virtually incompressible material, such as diamond. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Diamond anvil cell」の詳細全文を読む スポンサード リンク
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