Holmium oxidation states

Holmium has an oxidation state of +3 that, on a limited basis, can form a few compounds with the halogens and oxygen. They are of no commercial uses, and most holmium is used for research purposes. 

There are three experimental studies on HoO by Kaledin and Shenyavskaya (1981), Liu et al. (1984) and Linton and Liu (1988). The paper by Liu et al. (1984) provides a comprehensive table of known electronic states of HoO. The paper of Linton and Liu (1988) deals primarily with the rotational and hyperfine structure in holmium oxide. They have compared the observed and computed hyperfine constants of Xj 8.5, Xj 7.5 and Wj 6.5 /2 states of HoO. 

The lutetium hahdes (except the fluoride), together with the nitrates, perchlorates, and acetates, are soluble in water. The hydroxide oxide, carbonate, oxalate, and phosphate compotmds are insoluble. Lutetium compounds are all colorless in the solid state and in solution. Due to its closed electronic configuration (4f " ), lutetium has no absorption bands and does not emit radiation. For these reasons it does not have any magnetic or optical importance, see also Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Neodymium Praseodymium Promethium Samarium Terbium Ytterbium. 

Few lanthanide elements may be oxidized to the tetravalent state and stabilized, almost exclusively, in fluorides and oxides. These are the elements cerium, terbium, praseodymium, dysprosium, neodymium, holmium, for example all in the ternary fluorides CS3RF7 (Hoppe and Roedder 1961). There are also hints at pentavalent praseodymium, CsPrFe would be the example (Hoppe 1980). 

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