TY  - JOUR
  - Barry, L; Holmes, JD; Otway, DJ; Copley, MP; Kazakova, O; Morris, MA
  - 2010
  - February
  - Journal of Physics-Condensed Matter
  - Unusual magnetism in templated NiS nanoparticles
  - Validated
  - ()
  - 22
  - 7
  - Nanostructured NiS was prepared by inclusion into anodic alumina templates. The resultant particles were found to be stoichiometric and highly crystalline. The particles displayed small particle superparamagnetism, and a low temperature (at 48 K (T-sg)) spin-freezing phenomenon (a spin-glass) and higher temperature (170 K) thermal blocking of small particle magnetic moment fluctuations were both observed for the first time for a sulfide material. Very unusually, these NiS materials are quite distinct from antiferromagnetic nanoparticulate sulfide materials, as they display a high temperature ferromagnetic-like phase. The saturation magnetization, the remanent magnetization, the coercivity and the ferromagnetic mass susceptibility were measured as 0.58 emu g(-1) (at 100 K), 0.19 emu g(-1), 219.5 Oe (at 170 K) and similar to 900 x 10(-6) emu Oe(-1) g(-1) respectively and these are consistent with a moderately strong ferromagnetism. The materials had an unexpectedly high Curie temperature of 390 K. The decrease of the saturation magnetization value at 30 K suggests that the ferromagnetic response is a surface phenomenon and the high coercivity of the paramagnetic component well above T-sg suggests that the core can be described as superparamagnetic.
  - 0953-8984
  - http://iopscience.iop.org/0953-8984/22/7/076001
DA  - 2010/02
ER  - 

@article{V17688922,
   = {Barry, L and  Holmes, JD and  Otway, DJ and  Copley, MP and  Kazakova, O and  Morris, MA},
   = {2010},
   = {February},
   = {Journal of Physics-Condensed Matter},
   = {Unusual magnetism in templated NiS nanoparticles},
   = {Validated},
   = {()},
   = {22},
   = {7},
   = {{Nanostructured NiS was prepared by inclusion into anodic alumina templates. The resultant particles were found to be stoichiometric and highly crystalline. The particles displayed small particle superparamagnetism, and a low temperature (at 48 K (T-sg)) spin-freezing phenomenon (a spin-glass) and higher temperature (170 K) thermal blocking of small particle magnetic moment fluctuations were both observed for the first time for a sulfide material. Very unusually, these NiS materials are quite distinct from antiferromagnetic nanoparticulate sulfide materials, as they display a high temperature ferromagnetic-like phase. The saturation magnetization, the remanent magnetization, the coercivity and the ferromagnetic mass susceptibility were measured as 0.58 emu g(-1) (at 100 K), 0.19 emu g(-1), 219.5 Oe (at 170 K) and similar to 900 x 10(-6) emu Oe(-1) g(-1) respectively and these are consistent with a moderately strong ferromagnetism. The materials had an unexpectedly high Curie temperature of 390 K. The decrease of the saturation magnetization value at 30 K suggests that the ferromagnetic response is a surface phenomenon and the high coercivity of the paramagnetic component well above T-sg suggests that the core can be described as superparamagnetic.}},
  issn = {0953-8984},
   = {http://iopscience.iop.org/0953-8984/22/7/076001},
  source = {IRIS}
}