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For many years, the International Union of Pure and Applied Chemistry (IUPAC) sponsored a non-critical compilation of metal complex equilibrium constants. The result was the publication of several volumes containing stability constants. In 1990, a computerised database containing the values from the IUPAC volumes was created by L. Pettit. The database – known as SC-Database – was distributed by Pettit’s company Academic Software and was kept up to date with new values from the literature with the help of an extended team. The SC-Database was still being distributed by Academic Software until 2016–17 but is no longer available from any source.

Here the result of data queries for most elements in the periodic in pdf format. Still investigating how to extract protonation constants for organic ligands. Data for Cu(II), Ni and Zn are incomplete due to the limit of 4999 experiments that can be exported at once from the SC-Database. Total number of Cu(II) experiments is 10906, Ni 6750 and Zn 6107.

H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac
Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr