Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Improved First-Principles Calculation of the Third Virial Coefficient of Helium

Published

Author(s)

Giovanni Garberoglio, Michael R. Moldover, Allan H. Harvey

Abstract

We employ state-of-the-art pair and three-body potentials for helium to calculate its third density virial coefficient C(T) with uncertainties much smaller than those of the best experimental results, and approximately one-fourth the uncertainty of our previous work. We have extended our results in temperature down to 2.6 K, incorporating the effect of spin statistics which become important below approximately 7 K. Results are given for both the 3He and 4He isotopes. We have also calculated the third acoustic virial coefficient (gamma)a; our calculated values compare well with the limited experimental data available. A correlating nist-equation for C(T) of 4He is presented; differentiation of this nist-equation provides a reliable and simpler way of calculating (gamma)a.
Citation
Journal of Research (NIST JRES) -
Volume
116

Keywords

acoustic virial coefficients, calibration, density, helium, metrology, thermodynamic properties, virial coefficients
Created August 31, 2011, Updated February 19, 2017