Effect of [Fe(CN)6]4- substitutions on the spin-flop transition of a layered nickel phyllosilicate.
A 3 to 1 Ni/Si antiferromagnetic layered phyllosilicate, Ni(3)Si(C(3)H(6)NH(3))F(0.65)O(1.9)(OH)(4.45)(CH(3)COO)(1.1)·xH(2)O, was modified with K(4)[Fe(CN)(6)]·3H(2)O. This compound retained its ordering as proved by X-ray diffraction, while infrared spectra revealed the presence of [Fe(CN)(6)](4-) groups and X-ray photoelectron spectroscopy showed that the latter partially substitute the acetate groups. Both the parent and the modified compound are canted antiferromagnets with an anisotropy perpendicular to the layers and show spin-flop transitions. For the parent compound, a single step spin-flop occurs at H = 24 kOe. The modified compound shows increased antiferromagnetic canting and a two-step transition (H(1) = 24 kOe, H(2) = 48 kOe). These results testify to the existence of competing interactions that depend sensitively on the grafted species.
Department of Materials Science & Engineering, University of Ioannina, Ioannina, Greece. kdimos@cc.uoi.gr
Konstantinos
K
Dimos
Ioannis
I
Panagiotopoulos
Theodoros
T
Tsoufis
Régis Y N
RY
Gengler
Aliki
A
Moukarika
Petra
P
Rudolf
Michael A
MA
Karakassides
Thomas
T
Bakas
Dimitrios
D
Gournis