High pressure diamond anvil

Chronister E L and Crowell R A 1991 Time-resolved coherent Raman spectroscopy of low-temperature molecular solids in a high-pressure diamond anvil cell Chem. Phys. Lett. 182 27... 

In a rather complete study Russell et al. (1993) used a specially designed high-temperature/high-pressure diamond anvil cell to determine the phase diagram and stability fields between —125 and 340 °C and atmospheric pressure to 14.0 GPa. They characterized the C phase which exists at room temperature above 0.7 GPa pressure, and obtained FTIR spectra for all five polymorphs in various regions of... 

Ammonium dinitramide and dinitro azetidinium dinitramide For both of these materials the pressure/temperature and reaction phase diagram have been determined using a high-temperature-high-pressure diamond anvil cell with FTIR spectroscopy, Raman spectroscopy and optical microscopy. For ammoninm dinitramide energy dispersive X-ray diffraction was also employed (Russell et al. 1996, 1997). 

Starch shows absorption bands in the infrared that are sensitive to polymer conformation and hydration. Infrared spectroscopy and the high pressure diamond anvil cell can be used to follow in-situ the gelatinization of starch granules as a function of temperature and pressure... 

It may be argued [3] that the goal hardly attainable in the experiments using high-pressure diamond anvil cells could be more easily achieved in as simple an experiment as a conventional hardness test. The well-documented indentation size effect (ISE) [189] reveals itself in the following relation between the Meyer hardness HM (equivalent to the mean contact pressure) and the applied load P [190] ... 

Figure 90. Ultra-high pressure diamond anvils.

Zhal] XRD, high pressure (diamond anvil) 25°C, < 10 GPa, CuFe02... 

The spin and valence states of iron in the lower-mantle minerals have been investigated bya number of synchrotron X-ray and optical laser spectroscopic techniques in a high-pressure diamond anvil cell (DAC). Mossbauer spectroscopy has been instrumental in our understanding of this topic because this method is specific to Fe-containing minerals and provides hyperfine QS and CS parameters [5,19-22]. Specifically, synchrotron Mossbauer spectroscopy (SMS) with a highly intense and focused beam coupled with the X-ray transparent DAC permits in situ observations of the Mossbauer spectra with reasonable data collection times at extreme P-T conditions [20-22]. 

As noted above, a combination of high pressure diamond anvil techniques, all utilizing the ruby fluorescence method of pressure measurement, were used to carry out these experiments. These include (1) Fourier transform infrared (FTIR) spectroscopy for the kinetic measurements [9-11], (2) energy dispersive x-ray powder diffraction for crystallographic identification of the observed polymorphic forms and also compression measurements [12], (3) optical polarizing microscopy... 

---