Atomistic Simulation of Intrinsic Defects and Trivalent and Tetravalent Ion Doping in Hydroxyapatite

Table 5

Solution energies (eV) for substitution of the transition metals (M³⁺ = Fe, Mn, Cr, and Sc) and rare earth (M³⁺ = Lu and Yb) ions in HAP.

Mechanisms		Dopant
		Fe^3+	Mn^3+	Cr^3+	Sc^3+	Lu^3+	Yb^3+
Equation (1)		4.04	4.06	4.07	3.28	3.01	2.95
		7.63	7.11	5.20	3.68	1.49	3.65
Equation (2)		3.16	3.18	3.19	2.39	2.12	2.06
		6.75	6.23	4.32	2.79	1.47	3.65
Equation (3)		6.01	6.04	6.05	5.47	4.71	4.64
		10.50	9.84	7.46	5.96	2.79	5.52
Equation (4)		8.20	8.22	8.23	7.63	2.62	2.57
		10.90	10.50	9.07	7.93	1.46	3.10
Equation (5)		7.46	7.01	6.40	6.60	7.71	8.77
Equation (6)		6.85	6.39	5.79	5.98	7.09	8.15
Equation (7)		16.29	15.74	15.02	15.55	16.58	17.86
		21.34	20.79	20.07	20.60	10.10	11.37