Formation of five-coordinate cations between copper(II) polyamine complexes and inorganic anions. Standard thermodynamic functions in methanol at 25.deg.

Std. thermodynamic functions for the equil. [CuL2]2+ + X- .dblharw. [CuL2X]+ where L = en and H2N(CH2)3NH2 (tn) and for [CuL]2+ + X- .dblharw.[[CuLX]+ where L = triethylenetetramine (trien), H2N(CH2)2NH(CH2)3NH(CH2)2NH2 (2,3,2-tet), and H2N(CH2)3NH(CH2)3NH(CH2)3NH2 (3,3,3-tet) and X = I, SCN, and N3 were detd. in MOH at 25°. Equil. consts. were detd. spectrophotometrically. Heats of reaction were detd. directly by calorimetric titrn. Enthalpies of formation are all pos. or only slightly neg., while entropies are largely pos. For each Cu(II) polyamine complex the enthalpy (ΔH°) and entropy (ΔS°) changes decrease in the order N3- > I- > SCN-. With the same inorg. anion ΔH° and ΔS° decrease in the order [Cu-(en)2]2+ > [Cu(trien)]2+ ∼ [Cu(2,3,2-tet)]2+ > [Cu(tn)2]2+ > [Cu(3,3,3-tet)]2+.