Formation of Cu [II] -sulphato schiff base complexes spectral and magnetic studies

Cu[II]-sulphato Schiff base complexes of the type [Cu [SB]SO[4]]2H[2]O or [Cu[SB]SO[4] [H[2]O][2]],where [SB] is bidentate or tetradentate Schiff s base, were synthesized and characterized by elemental analysis, conductance measurement IR, electronic and electron paramagnetic resonance spectra as well as magnetic moments determination. Generally, the spectral results showed that Cu[II] ions are present in an axial elongated symmetry [D[4h]]. Moreover, the magnetic moment values [<1.74 B.M.] measured at room temperature and the g values suggest the presence of an appreciable metal - metal interaction

Formation constants of 3,5,7,2',4', pentahydroxyflavone-Nd-III complexes by spectrophotometric and potentiometric studies

Complex formation of Nd [III] with 3,5,7,2',4'-pentahydroxyflavone has been studied by spectrophotometric and potentiometric methods at 25C and at mu = 0.1 M using NaClO4. The metal forms 1:1 and 1:2 complexes. The protonation constants of morin and the stepwise stability constants of its Nd complex have been determined. Free energy changes during protonation of the ligand as well as during complex formation are reported. The solid complex was prepared and studied to ascertain the mode of bonding

Mechanism of extraction of Fe [III], Fe [II], Co [II] and Ni [II] by Di- [2-ethylhexyl] phosphoric acid from sulphuric acid medium

Distribution ratio, D, for iron, cobalt and nickel as a function of acidity and extractant molarity has been determined in a sulphate-di [2-ethylhexyl] phosphoric acid [DEHPA] system using benzene or 2-ehtyl hexanol as non polar and polar diluents respectively. The extractability of Fe [III] by DEHPA in benzene goes through a minimum with increasing acidity of the aqueous phase. The divalent ions Fe [II], Co [II] and Ni [II] seem to be poorly extracted at low acidities [0.5-IM] with the formation of M [HX2]. On the other hand, Fe [III] exhibited the highest value of D suggesting of its separation from these divalent ions With 2-ethyl hexanol, the distribution ratio for all ions are lower than in benzene and the extraction proceeds through chelate formation of Fex3 or MX2 for Fe [II], Ni [II] and Co [II].