THE SYNTHESIS AND CHARACTERIZATION OF LANTHANUM PHOSPHITE PHENYLPHOSPHONATE MIXED DERIVATIVES

Mixed derivatives of general formula La2(O3PH)3-x(O3PC6H5)x.yH2O have been synthesized from both aqueous and ethanolic solutions. The mixed derivatives are single phase layered compounds made up of randomly dispersed phosphite and phenylphosphonate groups throughout the layer, as determined by X-ray powder diffraction, IR, TGA and P-31 MAS NMR. Two representative mixed derivatives prepared in aqueous media, La2(O3PH)1.75(O3PC6H5)1.25.2.3H2O and La2(O3PH)2.36(O3PC6H5)0.64.1.9H2O), and one mixed derivative formed from ethanol solution, La2(O3PH)2.45(O3PC6H5)0.55.2.7H2O, are described in detail. The aqueous phase mixed derivatives have interlayer spacings (d) equivalent to phenyl-phenyl abutments (approximately 15 angstrom), whereas the phase formed in ethanol has a d-spacing consistent with a phosphite-phenyl abutment (approximately 11 angstrom). The factors involved in preparing mixed derivatives are discussed.