Table 1.

Decimal logarithms of overall protonation and formation constants in the Co(II)−AlaSal system, β_mlh = [M_mL_lH_h]/[M]^m[L]^l[H]^h at 25.0 ± 0.1 °C, I = 0.1 (KNO₃) and UV/Vis spectral data. Standard deviations in parentheses after overall protonation and stability constants refer to random errors only.

Species	log10 βmlh	Stepwise Dissociation Constants	Related Constants	λmax (εmax)
[L]2−				236 (8.2 × 103)
				292 (3.5 × 103)
[LH]−	10.73(1) (OH)	pKa3 10.73		237 (6.1 × 103)
				291 (2.6 × 103)
[LH2]	19.36(1) (NH2+)	pKa2 8.63 2		~240sh (4.1 × 103)
				274 (2.1 × 103)
[LH3]+	21.66(2) (COOH)	pKa1 2.30 3		~298sh (1.6 × 103)
σ; n1	5.82; 804
[CoL]	7.98(1)			508 (21)
[CoL2]2−	13.35(2)			483 (31)
[CoL3]4−	16.39(4)
[CoLH]+	13.64(10)		2.92 4
	21.78(2)		11.06 5
[CoL2H]−	26.35(4)		15.63 6
[CoL3H]3−
σ; n1	5.85; 455

¹σ—the value of the normalized sum of squared residuals; n—number of titration points; ² pK_a2 = ${\log }_{10}{K}_{{\mathrm{LH}}_2}^{\mathrm{LH}}=\log {\beta }_{{\mathrm{LH}}_2}-\log {\beta }_{\mathrm{LH}}$. ³ pK_a1 = ${\log }_{10}{K}_{{\mathrm{LH}}_3}^{{\mathrm{LH}}_2}=\log {\beta }_{{\mathrm{LH}}_3}-\log {\beta }_{{\mathrm{LH}}_2}$. ⁴ ${\log }_{10}{K}_{\mathrm{CoLH}}^{\mathrm{Co}}=\log {\beta }_{\mathrm{CoLH}}-\log {\beta }_{\mathrm{LH}}$. ⁵ ${\log }_{10}{K}_{{\mathrm{CoL}}_2\mathrm{H}}^{\mathrm{Co}}=\log {\beta }_{{\mathrm{CoL}}_2\mathrm{H}}-\log {\beta }_{\mathrm{LH}}$. ⁶ ${\log }_{10}{K}_{{\mathrm{CoL}}_3\mathrm{H}}^{\mathrm{Co}}=\log {\beta }_{{\mathrm{CoL}}_3\mathrm{H}}-\log {\beta }_{\mathrm{LH}}$.