Homologous Accommodation Methodology

Mendeleev drew five important conclusions from these rare-earth accommodations. The first one concerned the oxidation states of the rare-earth elements. Lanthanum, a typically trivalent element, was placed 

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Later, he accepted the elemental nature of the rare earths and he tried to place them in the periodic table according to a homologous accommodation methodology, as Mendeleev did. In 1876, Meyer placed cerium, erbium, and yttrium in the boron group as trivalent elements, but he placed lanthanum in the column of the tetravalent elements. 

History of the discovery of the rare-earth elements, 4 Ho Cs2, 122,126 Homologous accommodation methodology, 24 HOMO-LUMO, 115 gaps, 146... 

Bohuslav Brauner had approached the rare-earth crisis from a fradifional chemical poinf of view. Bofh the search for higher valencies and complicated atomic weight determinations had been central to his research during the last quarter of fhe nineteenfh century, but neither of fhese methodologies allowed to prove the validity of the homologous accommodation. Brauner s adherence to the Mendeleev method had led him to a... 

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