Table 6.

Lattice constants a ₀ and c ₀, bulk moduli B₀, heats of formation ▵_f H and oxygen vacancy energies E _v for the MgO crystal phases rock salt, wurtzite, zincblende, hcp, and cesium chloride determined in ReaxFF and DFT. ▵_f H and E _v were calculated using Equations (4) and (5). The experimental constants for the rock salt structure were adopted from Refs. [44] and [45].

Structure	Method	a 0 [Å]	c 0 [Å]	B 0 [GPa]	▵f H [eV]	E v [eV]
rock salt – Fm $\bar{3}$ m	ReaxFF	4.26		157.5	−5.49	−6.82
	DFT	4.25		154.6	−5.57	−6.71
	experiment[ 44 , 45 ]	4.21		155.0	−6.24
wurtzite – P 63 mc	ReaxFF	3.33	5.13	103.6	−5.34
	DFT	3.31	5.11	117.4	−5.43
zincblende – F $\bar{4}$ 3m	ReaxFF	4.60		122.4	−5.23
	DFT	4.61		117.4	−5.36
hcp – P 63 /mmc	ReaxFF	3.52	4.23	116.3	−5.48
	DFT	3.52	4.23	128.0	−5.50
cesium chloride – Pm $\bar{3}$ m	ReaxFF	2.59		210.4	−3.68
	DFT	2.65		142.2	−4.06