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  2. Transition metal - Wikipedia

    en.wikipedia.org/wiki/Transition_metal

    The typical electronic structure of transition metal atoms is then written as [noble gas]ns 2 (n − 1)d m. This rule is approximate, but holds for most of the transition metals. This rule is approximate, but holds for most of the transition metals.

  3. Electron configuration - Wikipedia

    en.wikipedia.org/wiki/Electron_configuration

    The naïve application of the aufbau principle leads to a well-known paradox (or apparent paradox) in the basic chemistry of the transition metals. Potassium and calcium appear in the periodic table before the transition metals, and have electron configurations [Ar] 4s 1 and [Ar] 4s 2 respectively, i.e. the 4s-orbital is filled before the 3d ...

  4. Electronic band structure - Wikipedia

    en.wikipedia.org/wiki/Electronic_band_structure

    Band structures of materials like Si, GaAs, SiO 2 and diamond for instance are well described by TB-Hamiltonians on the basis of atomic sp 3 orbitals. In transition metals a mixed TB-NFE model is used to describe the broad NFE conduction band and the narrow embedded TB d-bands.

  5. Metal L-edge - Wikipedia

    en.wikipedia.org/wiki/Metal_L-edge

    Metal L-edge spectroscopy is a spectroscopic technique used to study the electronic structures of transition metal atoms and complexes. This method measures X-ray absorption caused by the excitation of a metal 2p electron to unfilled d orbitals (e.g. 3d for first-row transition metals), which creates a characteristic absorption peak called the ...

  6. Surface properties of transition metal oxides - Wikipedia

    en.wikipedia.org/wiki/Surface_properties_of...

    The bulk electronic band structure of transition metal oxides consists of overlapping 2p orbitals from oxygen atoms, forming the lower energy, highly populated valence band, while the sparsely populated, higher energy conduction band consists of overlapping d orbitals of the transition metal cation. [21]

  7. Ligand field theory - Wikipedia

    en.wikipedia.org/wiki/Ligand_field_theory

    The size of Δ O determines the electronic structure of the d 4 - d 7 ions. In complexes of metals with these d -electron configurations, the non-bonding and anti-bonding molecular orbitals can be filled in two ways: one in which as many electrons as possible are put in the non-bonding orbitals before filling the anti-bonding orbitals, and one ...

  8. 18-electron rule - Wikipedia

    en.wikipedia.org/wiki/18-electron_rule

    The 18-electron rule is a chemical rule of thumb used primarily for predicting and rationalizing formulas for stable transition metal complexes, especially organometallic compounds. [1] 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 n s orbital ...

  9. Charge-transfer insulators - Wikipedia

    en.wikipedia.org/wiki/Charge-transfer_insulators

    In the charge-transfer case, the excitation happens from the anion (e.g., oxygen) p level to the metal d level with the charge-transfer energy Δ: +, =. U is determined by repulsive/exchange effects between the cation valence electrons. Δ is tuned by the chemistry between the cation and anion.