Dispersed molecular aggregates. 1. Synthesis and characterization of nanoparticles of Cu-2[Fe(CN)(6)] in H2O/AOT/n-heptane water-in-oil microemulsionmedia

Colloidal dispersions of Cu-2[Fe (CN)(6)] have been prepared in the nanodom ain water pools of water/ AOT/n-heptane water-in-oil microemulsion at vario us [water]/[AOT] mole ratios, iv, by reacting CuSO4 with K-4[Fe(CN)(6)]. Th e UV-visible absorption spectra of the isotropic molecular aggregates of Cu -2[Fe(CN)(6)] surrounded by a layer of amphiphile AOT have been measured. T he hydrodynamic diameter, diffusion coefficient, and the polydispersity ind ex of the colloidal dispersions prepared in the absence and presence of gel atin at different omega have been determined by the dynamic light scatterin g method; the static light scattering method has been employed to estimate the average particle weight of the dispersion. The formation of Cu-2[Fe(CN) (6)] in the dispersion has been established by X-ray diffraction measuremen ts. The size and shape of the colloidal dispersions and the isolated partic les have been examined by the transmission electron microscopy and scanning electron microscopy methods. The enthalpies of formation of Cu-2[Fe(CN)(6) ] in aqueous and in the microemulsion media have been calorimetrically dete rmined.