2007

Magnetic propertiesD 9000 Magnetic Disorder in the Frustrated Antiferromagnet Jarosite Arising from the

H3O+···OH- Interaction. — Jarosite solid solutions Kx(H3O)1-xFe3(OH)6(SO4)2

(0 < x < 1) are synthesized from aqueous solutions of Fe2(SO4)3 and K2SO4 (autoclave, 150 °C, 8 h). The samples are characterized by IR spectroscopy and magnetic suscep-tibility measurements. The ordering temperature Tmax of these spin-frustrated antiferro-magnets generally decrease with increasing content of interlayer hydronium ions. It is suggested that magnetic disorder resulting from an interaction between the interlayer hydronium ions and the interlayer Fe3+—OH-—Fe3+ groups is responsible for the de-crease in Tmax. — (GROHOL, D.; NOCERA*, D. G.; Chem. Mater. 19 (2007) 12, 3061-3066; Dep. Chem., MIT, Cambridge, MA 02139, USA; Eng.) — W. Pewestorf

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