Место издания:OOO «Адмирал Принт» ул. Барклая, 13/2, Москва, 129090
Первая страница:200
Аннотация:We present a simple method of predicting the stability constants logβ1 and logβ2 of the ML and ML2 complexes of lanthanide ions M (from Ce3+ to Lu3+) with diverse organic ligands (L) in water derived from linear free energy relationships. This method assesses the stability constants within predictable uncertainties compatible with those in known experimental values for most ligands. Two complexation characteristics e1 and e2 for every lanthanide ions were derived for an accurate prediction of stability constant for jth lanthanide ion using stability constant for ith lanthanide ion by the relationships logβ1j = e1j/e1i*logβ1i and logβ2j = e2j/e2i*logβ2i for given ligand. Three thousands of new logβ1 values and one thousand of new logβ2 values of potential complexes were predicted for the numerous metal/ligand combinations. The standard deviation of the predictions varies from 0,3 to 1,0 for logβ1 and from 0,4 to 1,2 for logβ2 as a linear function of the difference of ionic radii (∆rM) of two metal ions involved in the calculations: s1 = 0,27 + 4,25∆rM for
logβ1 and s2 = 0,39 + 5,16∆rM for logβ2 . The characteristics e1 and e2 correlate with ionic radii for lanthanide ions. Studied experimental data included 2854 logβ1 values for 445 organic ligands and 947 logβ2 values for 156 organic ligands and 13 metal datasets.
A predictor of the stability constants logβ1 (logβ2) of the ML (ML2) complexes of lanthanide ions M3+ with diverse organic ligands (L) in water was created on the base of the complexation characteristics e1 and e2 . The predictor is freely available as the
program LanComSim (Lanthanide Complexation Similarity) under Windows operating systems.