A new form of the semiempirical equation of state for the liquid phase of helium-4 is proposed that is based on the assumption that the structure of this phase consists of a mixture of dielectric and metallic components. It is postulated that solid dielectric helium with density higher than 5.3 g/cm³ becomes a metal. The values of the parameters of the equations of state for both solid phases and the liquid phase of helium are calculated. The unknown values of the initial data for helium are taken by analogy with the parameters for deuterium. The phase diagram, shock adiabat, isentropes, isotherms, and electrical conductivity in these processes are calculated with the use of the equations of state of solid and liquid phases of helium-4. The results of calculation are compared with experimental data in the range of pressures of up to 35 GPa for an isotherm, up to 150 GPa for a shock adiabat, up to 42 GPa for the melting curve, and up to 2000 GPa for isentropes, and showed quite satisfactory agreement. Numerical extrapolation of the melting curve is performed to a range of ultrahigh pressures of up to 8000 GPa.

中文翻译：

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介电和金属氦4的状态方程和相图

提出了一种氦4液相半经验状态方程的新形式，其假设是该相的结构由电介质和金属成分的混合物组成。假定密度大于5.3 g / cm ^3的固体介电氦变成金属。计算氦的固相和液相的状态方程的参数值。氦的初始数据的未知值类似于氘的参数。这些过程中的相图，冲击绝热，等熵，等温线和电导率是使用He-4的固相和液相状态方程来计算的。计算结果与实验数据进行了比较，在等温线压力高达35 GPa，冲击绝热线压力高达150 GPa，熔解曲线压力高达42 GPa，等熵线压力高达2000 GPa的范围内，以及表现出令人满意的协议。熔融曲线的数值外推是在高达8000 GPa的超高压范围内进行的。