Table 2. Change of thermodynamic properties in the FCC-SI to P2₁/c-SI transition.

ΔH	−0.23 eV mol−1
ΔV	−0.19 Bohr3 per mol
PΔV	−0.28 eV mol−1
ΔU	+0.05 eV mol−1

The change of specific enthalpy (H), volume (V) and internal energy (U) across the transition at P=1.6 TPa and T=1,900 K. The enthalpy difference is mainly due to the PΔV term, which in turn is due to the higher density in P2₁/c-SI.