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… 

Kinetics of the bcc–hcp transition in He4 off the melting curve

The kinetics of the bcc–hcp structural phase transition in He4 is investigated by the method of precision barometry in the pressure range 25–31 bar and temperature range 1.25–1.90K. Under

The Universality of Energy Spectrum of Phonon and Vacancy Excitations in Solid Helium

Abstract The most careful measurements on the specific heat C(T) and dP/dT (P is the pressure, T is the temperature) are analysed using a model where the thermodynamic properties of 3He and 4He

Measurements of the Specific Heat of Liquid and Solid 4He in a Confined Geometry at Low Temperatures

We present the results of specific heat measurements in liquid (0.43 and 21 bars) and solid hcp (20.9 cm3/mole) 4He in the temperature range 100 mK to ≈ 2 K. For the case of the liquid, we were

Direct measurements of thermal vacancies in BCC4He

X-ray lattice parameters of bcc4He crystals in contact with superfluid4He were measured with 300 ppm accuracy in the temperature range 1.494–1.711 K, corresponding to solid molar volumes between

Hysteresis of the bcc–hcp transition in a solid mixture of He3 in He4

Hysteresis of the bcc–hcp transition is observed by precision barometry in samples of a solid mixture of 1% He3 in He4 grown by the capillary blocking method. It is shown that the lines of

Kinetic processes at the triple points on the melting curve of 4He

The kinetics of a bcc–hcp structural phase transition on the melting curve of 4He near the triple points (bcc–hcp–He II and bcc–hcp–He I) in the temperature range 1.25–2.0 K is investigated. The

The bcc-hcp Phase Transition in 4He: Comparison with the Theory of Homogeneous Nucleation

Abstract Precise pressure experiments in supercooled bcc 4He are carried out under cooling along an isochore near an equilibrium line of the bcc-hcp structural phase transition. It is established

Kinetics of nucleation during the bcc-hcp structural transition in solid helium

The nucleation kinetics of the hcp phase in the supercooled bcc phase of solid 4He and a 3He-4He solution containing 1% 3He is studied experimentally. Precision measurements of the pressure in the

Anomalous temperature dependence ofD andT2 for dilute solutions of3He in solid4He

Results of measurements of the spin diffusion coefficientD and NMR relaxation timesT1,T2, and T1p are presented for a range of fractional3He concentrations 1 × 10−4≤x3≤2.5 × 10−3 in solid4He at molar

Contribution of phonon and vacancion excitations to the thermodynamic properties of solid helium

Precision measurements of the temperature dependence of the pressure are made on high-quality crystals of He4 and He3–He4 solutions grown at a constant volume. The phonon and vacancion contributions



The thermodynamic properties of fluid helium

  • R. W. HillO. V. Lounasmaa
  • Physics, Chemistry
    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 measured

Pressure-volume-temperature relations in liquid and solid4He

PVT relations in liquid and solid4He near the melting curve were measured over 0.3–2.0 K with a cell that used diaphragms for pressure and volume variation. The results were largely self-consistent


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 melting

Heat Capacity of the ? Phase of He^{4}

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 the