Package EquationOfStateRecipes.jl provides some default themes for plotting an EquationOfStateOfSolids. First, try to install the Plots.jl package by

julia> using Pkg

julia> Pkg.add("Plots")

julia> using Plots

Then install EquationOfStateRecipes.jl with

julia> Pkg.add("EquationOfStateRecipes")

julia> using EquationOfStateRecipes

Finally, load EquationsOfStateOfSolids.jl and plot:

julia> using EquationsOfStateOfSolids

julia> eos = EnergyEquation(Murnaghan(224.501825u"bohr^3", 8.896845u"GPa", 3.723835, -323.417686u"Ry"));

julia> plot(eos)

julia> plot!(eos, (0.8:0.01:1.2) * eos.param.v0)

julia> scatter!(eos, (0.5:0.1:1) * eos.param.v0)


Have fun!