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. Author manuscript; available in PMC: 2011 Jan 1.
Published in final edited form as: J Chem Theory Comput. 2010;6(3):774–786. doi: 10.1021/ct900576a

Table 2.

The properties of alkali cations, halide anions and divalent cations with Drude polarizable models.

Ion Umina dminb ΔHc rmax gmax rmin gmin Nc Dd ΔGe ΔΔGf
Li+ −35.9 (−35.2) 1.91 (1.87) −35.6 (−34.0,−34.0) 2.02 12.50 2.56 0.00 4.0 1.30 (1.03) −120.5 −24.2 (−23.8~-26.2)
Na+ −24.6 (−24.3) 2.25 (2.26) −24.4 (−24.0,−25.0) 2.38 7.42 3.24 0.20 5.6 1.58 (1.33) −96.3 −17.3 (−16.7~−17.7)
K+ −17.9 (−17.8) 2.62 (2.64) −17.6 (−17.9,−18.1) 2.74 4.80 3.56 0.45 6.9 2.20 (1.98) −78.6 −5.2 (−4.9~−5.4)
Rb+ −15.7 (−16.1) 2.79 (2.79) −15.2 (−15.9,−16.0) 2.90 4.04 3.80 0.62 8.1 2.44 (2.07) −73.7 −7.1 (−5.5~−7.7)
Cs+ −13.3 (−14.1) 3.05 (2.99) −12.5 (−13.7, —) 3.16 3.25 4.10 0.75 9.7 2.56 (2.06) −66.5
F −23.5 (−25.9) 2.53 (2.44) −23.2 (−23.3,−23.3) 2.72 4.77 3.34 0.37 5.5 1.33 (1.48) −108.0 −30.0 (−13.4~−30.6)
Cl −14.0 (−14.4) 3.09 (3.11) −13.7 (−13.1,−14.4) 3.16 3.15 3.78 0.72 6.5 1.82 (2.03) −78.4 −6.5 (−3.3~−6.9)
Br −12.4 (−12.7) 3.26 (3.26) −11.9 (−12.6,−13.0) 3.28 2.70 3.96 0.75 6.8 1.85 (2.08) −71.6 −8.5 (−7.7~−11.1)
I −10.2 (−10.6) 3.56 (3.50) −9.7 (−10.2,−10.5) 3.50 2.28 4.16 7.13 7.1 2.02 (2.05) −63.1
Zn2+ −100.0 (−96.3) 1.82 (1.86) −99.4 (−103.1) 2.14 17.2 3.08 0.0 6.0 0.61 (0.70) −460.2 −90.3 (−107.6)
Mg2+ −89.4 (−77.9) 1.86 (1.93) −89.0 (−81.8) 2.06 19.0 2.72 0.0 6.0 0.82 (0.71) −447.2 −77.3 (−77.7~−80.3)
Ca2+ −55.6 (−54.9) 2.18 (2.25) −55.1 (−56.5) 2.28 16.9 2.76 0.0 6.0 0.96 (0.79) −369.9 −32.7 (−29.8~32.9)
Sr2+ −45.2 (−40.6) 2.30 (2.52) −44.7 (−) 2.42 11.9 3.20 0.0 7.2 0.96 (0.79) −337.2 −27.2 (−27.9~31.1)
Ba2+ −37.7 (−34.0) 2.56 (2.73) −37.3 (−) 2.68 10.4 3.30 0.1 8.2 0.97 (0.85) −310.0
a

The reference binding energy in parentheses Umin of monovalent monohydrates are taken from various sources: 29 Li+; 73 Na+; 74 K+; 75 Rb+; 74 Cs+; 74 F; 76 Cl; 76 Br; 76 I; 76 The reference values for divalent were obtained with MP2 calculations with basis set 6-311++G(3df,3pd) for hydrogen, oxygen, Mg2+, Ca2+, and Zn2+ and LANL2DZ pseudopotential and associated basis set for Sr2+ and Zn2+. The energies are in kcal/mol.

b

The reference distance in parentheses Rmin of the alkali cations are taken from various sources 29 while those of the halide anions are taken from. 76 The reference values for divalent cations were obtained from MP2 calculations (See a for details). The distances are in Å.

c

The reference enthalpies in parentheses ΔH for the monovalent monohydrates are taken from the experimental studies. 71,72 The reference enthalpies in parentheses ΔH for the divalent monohydrates are taken from the theoretical study. 87 The enthalpies are in kcal/mol.

d

The experimental self diffusion coefficients are taken from the Handbook of Chemistry and Physics. 95 The self diffusion coefficients are in 10−5cm2/s.

e

The real hydration free energies ΔGreal in kcal/mol are obtained from the intrinsic free energies from periodic boundary conditions (PBC) simulations corrected with the phase potential and entropy related contributions.

f

The experimental hydration free energy differences in kcal/mol for the monovalent ions are taken from, 72,78-83 while those for the divalent ions are taken from. 80,82,83 The entry for Zn2+ is defined as ΔGhydrreal(Zn2+)ΔGhydrreal(Ca2+).