Structural Characterization of Doped Calcium Tartrate Tetrahydrate

Crystals of calcium tartrate tetrahydrate were grown in silica gel medium in pure form and with barium, strontium, cobalt, nickel, manganese, zinc, and cadmium as dopants. The crystals, with formula DxCa1–x(C4H4O6).4H2O (where D=doping atom), were characterized by X-ray diffraction, photoelectron spectroscopy, and Raman spectroscopy. Some of the doping atoms are located in the host lattice and others are distributed at random positions, especially on the surface of the crystals. In the host lattice the doping atom replaces Ca when an earth alkaline atoms is used but occupies an interstitial site when a transition metal atom is used. The dielectric permittivity is higher in doped compounds.