Table 6.

Mg²⁺ and Mn²⁺ Ions in Different Ligand Environments^a

Me(ll)	L1	L2	R1b	R2c	ROwd	ΔE	ΔEZPC	ΔG	ΔΔGsole	ΔGaqf
Mg2+					2.11	−318.13	−303.18	−253.13	200.66	−52.46
Mg2+	DMP− OP		2.00		2.13	−199.99	−200.42	−197.06	190.50	−6.56
Mg2+	GUA N7		2.21		2.12	−44.27	−44.99	−40.81	83.89	43.08
Mg2+	GUA N7	DMP− OP	2.21	2.01	2.13	−223.91	−224.51	−217.52	231.73	14.21
Mn2+					2.21	−301.29	−288.19	−239.59	170.58	−69.01
Mn2+	DMP− OP		2.06		2.24	−199.90	−199.90	−196.23	164.30	−31.93
Mn2+	GUA N7		2.23		2.23	−46.36	−46.77	−42.27	40.76	−1.51
Mn2+	GUA N7	DMP− OP	2.26	2.06	2.26	−225.29	−225.54	−217.04	187.17	−29.87

^aShown are results for the ligand environments. [Me(L 1 · · · Ln)(H₂O)_6–n] for n = 0, 1 or 2. Metal–ligand distances are listed in Å. The energetic and thermodynamic quantities are in kcal/mol at 298.15 K and correspond to the ligand substitution reaction: [Me(L1 · · · Ln)(H₂O)_6–n] + nH₂O→ [Me(H₂O)₆] +L1 + · · · Ln, except for n = 0 (fully hydrated metal) in which case the thermodynamic data refers to the absolute ligand binding energy: [Me(H₂O) ₆] →Me + 6H₂O. Shown are the difference in electronic energy (ΔE), electronic energy with zero-point vibrational correction (ΔE_ZPC), gas-phase free energy (ΔG), solvation free energy (ΔΔG_sol) and free energy in aqueous solution (ΔG_aq).

^bMe(II) · · · L₁ bond length.

^cMe(II) · · · L₂ bond length.

^dMe(II) · · · O_W average bond length.

^eSolution-phase free energy correction (PCM).

^fSolution phase (water) free energy.