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Fundamental Equation of State for Deuterium



Ian A. Richardson, Jacob W. Leachman, Eric Lemmon


World utilization of deuterium is anticipated to increase with the rise of fusion energy machines such as ITER and NIF. We present a new fundamental equation of state for the thermodynamic properties of fluid deuterium. Differences between thermodynamic properties of orthodeuterium, normal deuterium, and paradeuterium are described. Separate ideal-gas residual functions were fitted for these separable forms together with a single real fluid residual. The equation of state is valid from the melting line to a maximum pressure of 2000 MPa and an upper temperature limit of 600 K, corresponding to available experimental measurements. The uncertainty in predicted density is 0.1 % in the region between 100 and 423 K. The uncertainties of vapor pressures and saturated liquid densities are 2 % and 3 %, respectively, while speed-of-sound values are accurate to within 1 % in the liquid phase.
J. Phys. & Chem. Ref. Data (JPCRD) -


deuterium, equation of state, normal deuterium, orthodeuterium, paradeuterium, thermodynamic properties


Richardson, I. , Leachman, J. and Lemmon, E. (2014), Fundamental Equation of State for Deuterium, J. Phys. & Chem. Ref. Data (JPCRD), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 21, 2024)


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Created February 26, 2014, Updated October 12, 2021