Covalent Embedding of Ni super(2+)/Fe super(3+) Cyanometallate Structures in Silica by Sol-Gel Processing

Compound [Ni(AEAPTS) sub(2)] sub(3)[Fe(CN) sub(6)] sub(2) (AEAPTS=N-(2-aminoethyl)-3-aminopropyltrimethoxysi lane), in which Ni super(2+) and Fe super(3+) ions are ferromagnetically coupled through cyano bridges, was prepared. Sol-gel processing of the AEAPTS derivative resulted in incorporation of the cyanometallate in silica. The obtained material is magnetically ordered below 22K with an effective magnetic moment mu sub(eff) of 4.46 mu sub(B) at room temperature, a maximum of 8.60 mu sub(B) at approximately 15K and a narrow hysteresis at 2K, with a saturation remanence of about 300emumol super(-1) and a coercitivity of 0.03T. Magnetic crowd: [Ni(AEAPTS) sub(2)] sub(3)[Fe(CN) sub(6)] sub(2) (AEAPTS=N-(2-aminoethyl)-3-aminopropyltrimethoxysi lane) was covalently tethered to silica gel. The obtained material is magnetically ordered below 22K with an effective magnetic moment mu sub(e)ffof 4.46 mu sub(B) at room temperature, a maximum of 8.60 mu sub(B) at approximately 15K, and a narrow hysteresis at 2K (saturation remanence approximately 300emumol super(-1), coercitivity 0.03T).