Synthesis Condition Dependence of
Magnetic Property of
Ni(OH)2 Monolayer Nanocluster
Synthesized from Sodium Metasilicate

Heat capacities, magnetic susceptibilities, and X-ray diffraction patterns of Ni(OH)2 monolayer nanoclusters (Ni-MNC) in amorphous SiO2 synthesized with various concentration ratios of NiCl2 and Na2SiO3 solutions were measured. The Ni-MNCs exhibited a broad heat capacity anomaly around 20 K. Magnetic entropies for the Ni-MNCs were smaller than the expected value for S = 1 spin systems (Rln3 = 9.13 J K−1 mol−1), which suggests that the Ni-MNCs show a spin-glass-like behavior. Magnetic susceptibility measurements indicated change of the blocking temperature where the ZFC and FC data branched, which is characteristic of spin glass systems. X-ray diffraction experiments showed the direct evidence that the sizes of the Ni-MNCs are different by the synthetic condition.

(by T. Maruoka & Y. Miyazaki)

	Fig. 1. Magnetic heat capacities of Ni-MNCs in the samples A, D, and F.		Fig. 2. Magnetic susceptibilities of Ni-MNCs in the sample A, B, C, D, E, and F. Blocking temperatures are indicated by arrows.
	Fig. 3. X-ray diffraction patterns of Ni-MNCs in the samples A, D, and F.