| Abstract
| - The assembly of two-dimensional cyanide-bridged FeIII−NiII square grid networks at the air−water interface andsubsequent transfer of these networks as isolated monolayer, isolated bilayer, and multiple bilayer (multilayer)films via the Langmuir−Blodgett technique results in novel low-dimensional systems in which the effects ofdimensionality on magnetic behavior in molecule-based materials can be observed. The magnetic response ofthese films between 2 < T< 300 K in dc fields from −50 < H< 50 kG and in 4 G ac fields from 1 Hz to 1 kHzare reported. The results show the presence of ferromagnetic domains with characteristic hysteresis in each of thethree systems. The magnetic response for all three samples is anisotropic with a stronger field-cooled magnetizationobserved when the planes of the films are aligned parallel to the applied field. Additionally, each of the threesamples shows frequency dependence in both the real and imaginary components of the ac susceptibility. Thisbehavior is interpreted as being characteristic of spin glass-type ordering of ferromagnetic domains to form acluster glass. A lower glass temperature (Tg) is observed in the isolated monolayer film relative to the bilayer andmultilayer samples. The bilayer sample shows two glass transitions at Tg1 = 3.8 K and Tg2 = 5.4 K, whereas onlyone transition at Tg = 5.4 K is observed in the multilayer sample. The different magnetic responses of the threefilms are attributed to different in-plane, interplane, and long-range dipolar exchange interactions.
- Two-dimensional cyanide-bridged FeIII-NiII square grid networks assembled at the air−water interface and subsequently transferred using the Langmuir−Blodgett technique as monolayer, bilayer, and multiple bilayer (multilayer) films result in novel low-dimensional systems in which the effects of dimensionality on magnetic behavior in molecule-based materials can be observed. Different magnetic responses of the three films are attributed to differences in the in-plane, interplane, and long-range dipolar exchange interactions.
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