What does PXRD stand for?

Hubbard (1971-1988) Single crystal and powder x-ray diffraction methods, software, standard reference materials, and reference patterns collection and evaluation.

Crystal structure determinations using powder X-ray diffraction data are the key to clarify the structural changes responsible for observed symmetry changes and to pinpoint the phase-transition mechanism(s), not only for natrolite but also for other framework silicate minerals.

These milestone achievements or "firsts" included: (1) the invention of the lever-arm type diamond anvil cell (DAC) in 1958; (2) the development of DAC technology for powder x-ray diffraction at high pressure in 1960; (3) the introduction of DAC methodology for single crystal x-ray diffraction at high pressure in 1964; (4) the invention of the optical fluorescence ruby method of pressure measurement in 1971; and (5) the discovery of hydrostatic pressure-transmitting media useful to unprecedented pressures for that time.