Nickel oxide antiferromagnetic

Before the discovery of antiferromagnetism, it was pointed out that, according to the Wilson theory of metals and insulators (Chapter 1), nickel oxide should be a metal—whereas it is a transparent insulator. The nickel ions should have eight d-electrons, and the only splitting of the d-band to be expected is into the eg and t2g bands, with four and six electrons. Peierls explained in 1938 how this... 

Mo3NiS4(H20)io] ", as its j0-MeC6H4SO3 salt, exhibited antiferromagnetism (/r = 0.11 BM at 2.0 K and 1.26 BM at 260.7 K) and was described formally as containing Ni Mo Mo 2. However, this contrasted with the snbstitu-tion behavior at the nickel center, which appeared to fimction more hke Ni, showing that it is difficult to precisely assign formal oxidation states in these clusters. 

Nickel(II) oxide crystallizes in the NaCl structure. Thin amorphous films of it exhibit electrochromic behavior and are antiferromagnetic at Tn = 247 °C. Nickel(II) oxide films with smooth surfaces and columnar structures of preferred (100) orientation on MgO(lll), Si(lll), soda lime glass, fused silica and stainless steel can be obtained by and... 

The water-insoluble, green NiO is obtained by thermal decomposition of NiC03 or Ni(N03)2 and crystallizes with the NaCl structure thin amorphous films of NiO exhibiting electrochromic behaviour (see Box 22.4) may be deposited by CVD (chemical vapour deposition, see Section 27.6) starting from [Ni(acac)2]. Nickel(II) oxide is antiferromagnetic... 

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