STUDY OF COMPLEX-FORMATION IN THE MANGANESE(II) AZIDE SYSTEM/

The complex formation between Mn(II) cations and N-3(-) anions was stu died in aqueous medium at 25 degrees C and ionic strength 2.0 M (NaClO 4). Data of average ligand number, (n) over bar (Bjerrum's function), were obtained from pH measurements on the Mn(II)/N-3(-)/HN3 system fol lowed by integration to obtain Leden's function, F-0(L). Graphical tre atment of data and a matrix solution of simultaneous equations have gi ven the following overall formation constants of mononuclear stepwise complexes: beta(1) = 4.15 +/- 0.02 M(-1), beta(2) = 6.61 +/- 0.04 M(-2 ), beta(3) = 3.33 +/- 0.02 M(-3), beta(4) = 0.63 +/- 0.01 M(-4). A lin ear plot of log K-n vs. (n-1) shows no change in the configuration dur ing complex formation. Slow spontaneous oxidation of solutions to Mn(I II) occurs when the N-3(-) concentration is greater than 1.0 M.