TECHNIQUES FOR STRUCTURAL STUDIES OF LIQUIDS AND AMORPHOUS MATERIALS BY NEUTRON DIFFRACTION AT HIGH PRESSURES AND TEMPERATURES

摘要

This paper describes new techniques which permit the study of liquids and amorphous materials using neutron diffraction at high pressures and high temperatures up to 6.5 GPa and 1000 K using the Paris-Edinburgh cell. The set-up is based on an internal heating system, and combines a novel encapsulation method and highly transparent sintered diamond anvils to maximise the signal from a sample of 60 mm{sup}3 volume. We describe in detail the experimental set-up, the operation conditions, and the procedure for absorption correction and background subtraction. The method is illustrated by recent data collected on D{sub}2O water at 6.5 GPa and 672 K.