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The sesquicarbides, Ln 2 C 3 can be formulated as Ln 4 (C 2) 3. These compounds adopt the Pu 2 C 3 structure [49] which has been described as having C 2 2− anions in bisphenoid holes formed by eight near Ln neighbours. [69] The lengthening of the C-C bond is less marked in the sesquicarbides than in the dicarbides, with the exception of Ce 2 ...
The sesquicarbides, Ln 2 C 3 can be formulated as Ln 4 (C 2) 3. These compounds adopt the Pu 2 C 3 structure [10] which has been described as having C 2 2− anions in bisphenoid holes formed by eight near Ln neighbours. [28] The lengthening of the C-C bond is less marked in the sesquicarbides than in the dicarbides, with the exception of Ce 2 ...
In chemistry, an unpaired electron is an electron that occupies an orbital of an atom singly, rather than as part of an electron pair. Each atomic orbital of an atom (specified by the three quantum numbers n, l and m) has a capacity to contain two electrons ( electron pair ) with opposite spins .
Most lanthanides can use only three electrons as valence electrons, as afterwards the remaining 4f electrons are too strongly bound: cerium is an exception because of the stability of the empty f-shell in Ce 4+ and the fact that it comes very early in the lanthanide series, where the nuclear charge is still low enough until neodymium to allow ...
The valence is the combining capacity of an atom of a given element, determined by the number of hydrogen atoms that it combines with. In methane, carbon has a valence of 4; in ammonia, nitrogen has a valence of 3; in water, oxygen has a valence of 2; and in hydrogen chloride, chlorine has a valence of 1.
The ground state term symbol is 5 I 4. [15] The sulfate is slightly soluble, like the other cerium group sulfates. Cell parameters have been calculated for its octahydrate; they lead to conclusion that the density of Pm 2 (SO 4) 3 ·8H 2 O is 2.86 g/cm 3. [16] The oxalate, Pm 2 (C 2 O 4) 3 ·10H 2 O, has the lowest solubility of all lanthanide ...
Valence bond theory complements molecular orbital theory, which does not adhere to the valence bond idea that electron pairs are localized between two specific atoms in a molecule but that they are distributed in sets of molecular orbitals which can extend over the entire molecule. Although both theories describe chemical bonding, molecular ...
The rule is based on the fact that the valence orbitals in the electron configuration of transition metals consist of five (n−1)d orbitals, one ns orbital, and three np orbitals, where n is the principal quantum number. These orbitals can collectively accommodate 18 electrons as either bonding or non-bonding electron pairs.