  This is the second paper of a series of our works on the self-similar
orbit-averaged Fokker-Planck (OAFP) equation and details physical properties of
isotropic pre-collapse solution. The fundamental core collapse process at the
late stage of relaxation evolution of spherical star clusters can be described
by the self-similar OAFP equation. The accurate spectral solution was found
recently in the first paper. The present work details the thermodynamic aspects
of the model based on the stellar DF obtained from the solution. Our
calculation shows the following local properties (i) Equation of state is
$p=1.0\rho/\chi_\text{esc}$ in the core where $p$ is the pressure, $\rho$ the
density and $\chi_\text{esc}$ the scaled escape energy, while it is
$p=0.5\rho^{1.1}/\chi_\text{esc}$ at large radii. (ii) If we consider the
center of the core is polytropic, the polytropic index is 177. Also, as a
global property we construct caloric curves of the model to discuss the heat
capacity together with Virial. Special focus is the cause of negative heat
capacity of the core; the well-relaxed core can be directly compared to the
isothermal sphere with positive heat capacity. Comparing our results to the
previous works, we conclude, in the self-similar evolution, the negative heat
capacity in the core holds due to collisionless and high-temperature stars that
experience a rapid change in mean field potential through stellar- and heat-
flows, rather than due to the (quasi-)isolation of the core from surroundings.
