Abstract
High-energy neutron-scattering experiments are reported on three samples of liquid natural neon. One was at 25.8 K at low pressure and two near 35 K were pressurized to densities differing by 9%. Measurements were made at wave-vector transfers Q in the range 200–280 , within the impulse approximation, with accounting for spectrometer resolution and multiple-scattering effects. Single-particle kinetic energies, 〈〉, were determined by assuming a Gaussian atomic momentum distribution. The value 〈〉/=52.8±3.7 K at 25.8 K is found to be somewhat larger than a deduction in the literature from experimental work at Q values below 100 . The difference between current measurements and the previous deduction can be attributed to the failure of previous measurements to operate within the impulse approximation. Our two values of 〈〉 near 35 K differ by (4±0.3)%, a small relative difference. A comparison of the present results for 〈〉 with calculated values dependent upon S(Q) measurements (and inferred pair-correlation functions) shows only qualitative agreement, as does a comparison with a published Wigner-Kirkwood expansion of the density matrix, using a Lennard-Jones potential.
- Received 19 November 1991
DOI:https://doi.org/10.1103/PhysRevB.45.9671
©1992 American Physical Society