Laser-heated diamond anvil cell

Very recently, Solozhenko [540] reported the high-pressure-high-temperature synthesis of cubic BC2N with in situ control of the reaction by x-ray diffraction measurement. The first high-density product has been obtained in a laser-heated diamond anvil cell (DAC). The starting material was g-BC N, prepared... 

W. A. Bassett and M. S. Weathers, Temperature measurement in a laser heated diamond anvil cell, in High-Pressure Research in Mineral Physics, M. H. Manghnani and Y. Syono, eds., American Geophysical Union, Washington, DC, 1987, pp. 129-134. 

Jephcoat, A. P., Besedin, S. P. (1996) Temperature measurement and melting determination in the laser-heated diamond anvil cell. Phil. Trans. Roy. Soc. A, 354, 133-60. 

The e - y transition boundary was determined by measuring the resistance changes during the transition in a high-compression belt apparatus (Bundy, 1965) and in an internally heated diamond-anvil cell (Boehler, 1986 Mao et al, 1987). The boundary was also determined by in situ X-ray diffraction measurements in an internally heated diamond-anvil cell (Boehler, 1986 Dubrovinsky et al, 1998), in a laser-heated diamond-anvil cell (Shen et al, 1998), and in a multi-anvil apparatus (Funamori et al, 1996 Lfchida et al, 2001). The boundaries determined by Mao et al. (1987), Shen et al (1998), and Lfchida et al (2001) are in good agreement, but are all at —75 K higher temperature (or —2 GPa lower pressure) than the boundary determined by Funamori et al. (1996), Boehler (1986), and Bundy (1965). 

Experiments have established that there are four polymorphs in solid iron (a-, y-, S-, and s-phases). Saxena et al (1993) proposed a fifth iron phase (/3-phase) based on changes in thermal emission while laser heating the sample in a diamond-anvil cell. Boehler (1993) also observed similar changes in optical properties of iron in the same P-T range. Subsequent in situ X-ray diffraction measurements in the laser-heated diamond-anvil cell supported the occurrence of this new iron phase, although the structure of this phase is still under debate (Saxena et al, 1996 Yoo et al, 1996 Andrault et al, 1997, 2000 Saxena and Dubrovinsky, 2000). However, this phase was not observed in... 

The eutectic temperamre of the Fe-S binary system has been measured in a multi-anvil apparatus to 25 GPa (Fei et al, 1997, 2000 Li et al, 2001), and in a laser-heated diamond-anvil cell to 62 GPa (Boehler, 1996). Within the common pressure range, the diamond-anvil cell results are higher than the multi-anvil apparams results by as much as 400°. Despite the discrepancies, the existing data show that between... 

W.R. Panero, R. Jeanloz, X-ray diffiaction patterns from samples in the laser-heated diamond anvil cell. J. Appl. Phys. 91(5), 2769-2778 (2002)... 

High-pressure mineral physics therefore is concerned with the characterization of the physical properties and stability fields of planetary materials under extreme pressure and temperature conditions. For example, conditions present at the centre of the earth are thought to be in excess of 300 GPa and 5000 K. Such conditions can at present be obtained by laser-heated diamond anvil cells or multianvil presses. Emphasis of current in situ diffraction... 

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