MOSSBAUER AND NMR-STUDY OF THE N-D-GLUCONYLGLYCINE COMPLEX OF DIMETHYLTIN(IV) AND THE ASCORBIC-ACID CHLORIDE MIXED COMPLEX OF IRON(II) IN SOLUTIONS FIXED AS NANOSIZE DROPLETS IN SOLID MATRICES

Combined NMR and Mossbauer investigations were performed on two coordi nation chemical models of biological interest: an aqueous solution of the N-D-gluconylglycine complex of dimethyltin(IV), and methanolic and aqueous solutions of the ascorbic acid-chloride mixed complex of iron (II). When these solutions were fixed as nanosize droplets in solid ma trixes, significant changes occurred in both the structure and the com position of the coordination spheres of the central atoms in the compl exes situated in the bulk positions with no direct connection to the s urfaces of the holes in the matrix. The phenomenon was attributed to t he significant decrease in solvent activity in the pores of the matrix due to the appreciable amount of surface-bound solvent in the system. The model mimics coordination chemical systems in cell tissues. (C) 1 997 Elsevier Science B.V.