Table 3: Stability constants of the ternary species in the CoII-DPA-dibasic acids and proton-association constants and their binary stability constants.


 System l p q ra log βb Δlog K Sc

 [Co(H2O)4]2 1 0 0 −1 −8.44(0.06) 9.6E−7
1 0 0 −2 −17.99(0.02)
 DPA 0 1 0 1 7.65(0.01) 2.4E−7
0 1 0 2 10.21(0.02)
 Co-DPA 1 1 0 0 4.55(0.02) 3.6E−7
 Oxalic acid 0 0 1 1 3.93(0.00) 1.3E−9
0 0 1 2 5.66(0.01)
 Co-Oxalic 1 0 1 1 3.45(0.05) 3.7E−7
 Co-DPA-Oxalic 1 1 1 0 8.97(0.02) 0.97 3.7E−7
 CBDC acid 0 0 1 1 5.68(0.01) 5.4E−8
0 0 1 2 8.80(0.02)
 Co-CBDC acid 1 0 1 0 2.55(0.03)
 Co-DPA-CBDC acid 1 1 1 0 8.70(0.09) 1.67 1.7E−7
 Malonic acid 0 0 1 1 5.21(0.00) 2.0E−9
0 0 1 2 7.61(0.01)
 Co-malonic 1 0 1 0 2.59(0.01) 3.3E−8
 Co-DPA-malonic 1 1 1 0 8.61(0.05) 1.47 1.7E−7
 Succinic acid 0 0 1 1 5.21(0.00) 5.3E−10
0 0 1 2 9.26(0.01)
 Co-Succinic 1 0 1 1 1.80(0.01) 1.4E−7
 Co-DPA-succinic 1 1 1 0 7.66(0.03) 1.31 3.5E−9
 Adipic acid 0 0 1 1 5.11(0.01) 3.3E−9
0 0 1 2 9.35(0.02)
 Co-adipic 1 0 1 1 1.61(0.02) 2.4E−8
 Co-DPA-adipic 1 1 1 0 7.48(0.04) 1.32 2.5E−9

al, p, q and r are the stoichiometric coefficients corresponding to CoII, DPA, dicarboxylic acids and H+, respectively;
bStandard deviation is given in parentheses;
cSum of square of residuals.