Thermodynamic properties of4He. II. The bcc phase and theP-T and V-T phase diagrams below 2 K

  title={Thermodynamic properties of4He. II. The bcc phase and theP-T and V-T phase diagrams below 2 K},
  author={James K. Hoffer and Walter R. Gardner and Charles Garrow Waterfield and Norman E. Phillips},
  journal={Journal of Low Temperature Physics},
The constant-volume heat capacity of 4He has been measured at molar volumes from 20.45 to 29.71 cm3/mole in the temperature range from 0.3 to 4 K. The entropy has been obtained as a function of volume and temperature by extrapolation of the data to 0 K. The P-T equilibrium curves below 2 K were obtained from the volume dependence of the entropy in the two-phase regions. The V-T curves were obtained above 1.25 K by observation of heat capacity discontinuities at the phase boundaries and below 1… Expand
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  • Medicine, Physics
  • Royal Society Open Science
  • 2019
The critique of the Debye theory of specific heat and the Born–von Karman model of the lattice dynamics is given and the explanation of the correlation of the ‘boson peak’ temperature with the shear velocity is proposed. Expand
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  • R. W. Hill, O. V. Lounasmaa
  • Physics
  • Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
  • 1960
Measurements have been made from which all the thermodynamic properties of fluid helium can be calculated in the temperature range from 3 to 20 °K and up to 100 atm pressure. The quantities measuredExpand
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In the course of melting He/sup 4/ for measurements on the specific heat of liquid He/sup 4/ at temperatures below 1 l K under pressure, evidence for a minimum in the melting curve at 0.76 l K wasExpand
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Melting properties of He3 and He4 up to 3500 kg/cm2
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Using a phenomenological approach, it is shown first that solid He/sup 4/ in equilibrium with liquid He/sup 4/ II along the phase separation line, as well as at pressures somewhat above the meltingExpand
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Abstract This is the first of a series of two papers dealing with measurements of the isobaric thermal expansion coefficient, α p , of compressed He II. In this paper we describe the experimentalExpand
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The properties of the phase of He/sup 4/ were investigated to determine the lattice heat capacity difference of the bodycentered-cubic and hexagonal-close -packed phases, the isotope effect in theExpand
Abstract The entropies of solid 4He, liquid 4He and their two-phase mixtures, obtained from constant-volume heat capacity measurements, have been used to construct the low-temperature phase diagrams.