Direct measurements of the constant-volume heat capacity of solid parahydrogen from 22. 79 to 16. 19 cm/sup 3//mole and the resulting equation of state

Journal Article · Sat Mar 15 00:00:00 EST 1980 · Phys. Rev., B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.21.2533· OSTI ID:5471424

Krause, J K; Swenson, C A

The constant-volume heat capacity of solid parahydrogen ( p-H/sub 2/) has been measured directly from below4 K to the melting line for six molar volumes (22.787 to 16.19 cm/sup 3//mole). These data have been analyzed using the Mie-Grueneisen equation of state (EOS) to give the volume and temperature dependence of the Grueneisen parameter and the EOS for p-H/sub 2/, as well as the volume dependence of the quadrupole-quadrupole interaction parameter for orthohydrogen impurities. Good agreement is found with earlier 4-K high-pressure compression data, and reasonable agreement with direct strain-gauge measurements of P (V,T). The thermodynamic properties for solid p-H/sub 2/ at P=0 are obtained by extrapolation to larger molar volumes, with the T=0, P=0 equilibrium volume given as 23.234 ( +- 0.05) cm/sup 3//mole and the triple-point volume of the solid as 23.48 ( +- 0.05) cm/sup 3//mole. The rather large temperature dependence of the Grueneisen parameter which results from a comparison with high-pressure melting-line data is discussed in terms of an explicit temperature dependence of the lattice vibration spectrum. No indications were found for phase transitions in solid p-H/sub 2/, nor for premelting anomalies.

• Research Organization: Ames Laboratory-USDOE and Department of Physics, Iowa State University, Ames, Iowa 50011
• OSTI ID: 5471424
• Journal Information: Phys. Rev., B: Condens. Matter; (United States), Vol. 21:6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
HYDROGEN
EQUATIONS OF STATE
GRUENEISEN CONSTANT
LATTICE VIBRATIONS
QUADRUPOLE MOMENTS
SPECIFIC HEAT
TEMPERATURE DEPENDENCE
ULTRALOW TEMPERATURE
VERY HIGH PRESSURE
CRYOGENIC FLUIDS
ELEMENTS
EQUATIONS
FLUIDS
NONMETALS
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
360603* - Materials- Properties