While these compounds do exist, analogous chemicals that contain lanthanum, praseodymium, gadolinium, holmium, terbium, or ytterbium have not been discovered, as of 2008.
en.wikipedia.org They determined eka-ytterbium properties, consistent with nobelium as the heavier homologue.
en.wikipedia.org Mixtures of powdered ytterbium with polytetrafluoroethylene or hexachloroethane burn with a luminous emerald-green flame.
en.wikipedia.org The fluorescence of fluorite may be due to mineral impurities such as yttrium, ytterbium, or organic matter such as volatile hydrocarbons in the crystal lattice.
en.wikipedia.org The researchers also want to add traces of further elements to the ytterbium rhodium silicide, which would probably change its electronic properties considerably.
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