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  2. Lanthanide - Wikipedia

    en.wikipedia.org/wiki/Lanthanide

    The properties of the lanthanides arise from the order in which ... Monazite is a phosphate of numerous group 3 + lanthanide + actinide metals and mined especially ...

  3. Actinide - Wikipedia

    en.wikipedia.org/wiki/Actinide

    Actinides have similar properties to lanthanides. Just as the 4f electron shells are filled in the lanthanides, the 5f electron shells are filled in the actinides. Because the 5f, 6d, 7s, and 7p shells are close in energy, many irregular configurations arise; thus, in gas-phase atoms, just as the first 4f electron only appears in cerium, so the ...

  4. Lanthanide compounds - Wikipedia

    en.wikipedia.org/wiki/Lanthanide_compounds

    Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]

  5. Actinide chemistry - Wikipedia

    en.wikipedia.org/wiki/Actinide_chemistry

    The possibility of using unique properties of lanthanides in the nanotechnology is demonstrated. The origination of linear and nonlinear optical properties of lanthanide compounds with phthalocyanines, porphyrins, naphthalocyanines, and their analogs in solutions and condensed state and the prospects of obtaining novel materials on their basis ...

  6. Group 3 element - Wikipedia

    en.wikipedia.org/wiki/Group_3_element

    Due to the effects of the lanthanide contraction, yttrium and lutetium are very similar in properties. Yttrium and lutetium have essentially the chemistry of the heavy lanthanides, but scandium shows several differences due to its small size. This is a similar pattern to those of the early transition metal groups, where the lightest element is ...

  7. Actinide concept - Wikipedia

    en.wikipedia.org/wiki/Actinide_concept

    The actinide concept explained some of the observed properties of the first few actinides, namely the presence of +4 to +6 oxidation states, and proposed hybridization of the 5f and 6d orbitals, whose electrons were shown to be loosely bound in these elements. It also supported experimental results for a trend towards +3 oxidation states in the ...

  8. Thorium compounds - Wikipedia

    en.wikipedia.org/wiki/Thorium_compounds

    While the later actinides from americium onwards are predominantly trivalent and behave more similarly to the corresponding lanthanides, as one would expect from periodic trends, the early actinides up to plutonium (thus including thorium and uranium) have relativistically destabilised and hence delocalised 5f and 6d electrons that participate ...

  9. Main-group element - Wikipedia

    en.wikipedia.org/wiki/Main-group_element

    Sometimes groups 3 and 12, as well as the lanthanides and actinides (the two rows at the bottom), are also included in the main group. In chemistry and atomic physics , the main group is the group of elements (sometimes called the representative elements ) whose lightest members are represented by helium , lithium , beryllium , boron , carbon ...