Chemometric Investigation of Complex Equilibria in Solution Phase. Part-V. Correlation of Formation Constants of Manganese(II) or Zinc(Il) Complexes of AADH/FAH with Co-solvent Characteristics

School of Chemistry, Andhra University, Visakhapatnam-530 003 Manuscript received 23 November 1993. revised 31 May 1994, accepted 17 June 1994 The stoichiumetric composition and extent of formation of the complex species formed in aquo-organic media in the interaction of ZuII or MnII with AADH or FAH, is a multivariate chemical task. The primary data (pH versus volume of NaOH) under varying ratios of TLO to TMO and co-solvent content for each of the metal-ligand systems) was subjected to pre-processing to enhance the information to noise ratio. The initial approximate constants for protonated species, stoichiometric coefficients and a set of models to be tested were arrived by a heuristic approach. The MINIQUAD 75 program having the advantages of steepest gradient, Marquardt algorithm was used to arrive at the best lit chemical model in each of the systems. The different trends in the distribution of the species (3D plots) under experimental variables (total concentrations of metal and ligand) are of practical utility in preparative chemistry to obtain optimum concentrations. The change in the number of water molecules associated with each of the equilibria is obtained by linear regression of transformed equation