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  2. Transition metal complexes of phosphine oxides - Wikipedia

    en.wikipedia.org/wiki/Transition_metal_complexes...

    Transition metal complexes of phosphine oxides are coordination complex containing one or more phosphine oxide ligands. Many phosphine oxides exist and most behave as hard Lewis bases . Almost invariably, phosphine oxides bind metals by formation of M-O bonds.

  3. Crystal field theory - Wikipedia

    en.wikipedia.org/wiki/Crystal_field_theory

    For example, in an octahedral case, the t 2g set becomes lower in energy than the orbitals in the barycenter. As a result of this, if there are any electrons occupying these orbitals, the metal ion is more stable in the ligand field relative to the barycenter by an amount known as the CFSE.

  4. Polyoxometalate - Wikipedia

    en.wikipedia.org/wiki/Polyoxometalate

    The phosphotungstate anion, an example of a polyoxometalate. In chemistry, a polyoxometalate (abbreviated POM) is a polyatomic ion, usually an anion, that consists of three or more transition metal oxyanions linked together by shared oxygen atoms to form closed 3-dimensional frameworks.

  5. Isomorphism (crystallography) - Wikipedia

    en.wikipedia.org/wiki/Isomorphism_(crystallography)

    Forsterite. In chemistry, isomorphism has meanings both at the level of crystallography and at a molecular level. In crystallography, crystals are isomorphous if they have identical symmetry and if the atomic positions can be described with a set of parameters (unit cell dimensions and fractional coordinates) whose numerical values differ only slightly.

  6. 18-electron rule - Wikipedia

    en.wikipedia.org/wiki/18-electron_rule

    Compounds that obey the 18-electron rule are typically "exchange inert". Examples include [Co(NH 3) 6]Cl 3, Mo(CO) 6, and [Fe(CN) 6] 4−.In such cases, in general ligand exchange occurs via dissociative substitution mechanisms, wherein the rate of reaction is determined by the rate of dissociation of a ligand.

  7. Surface properties of transition metal oxides - Wikipedia

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

    Examples of nonpolar surfaces include the rocksalt (100) surface, the rutile (100), (110) and (001) surfaces and the pervoskite (100) surface. [2] An example of a polar surface is the rocksalt (111) surface. [2] In general, a polar surface is less stable than a nonpolar surface because a dipole moment increases the surface Gibbs energy.

  8. Fajans' rules - Wikipedia

    en.wikipedia.org/wiki/Fajans'_rules

    The "size" of the charge in an ionic bond depends on the number of electrons transferred. An aluminum atom, for example, with a +3 charge has a relatively large positive charge. That positive charge then exerts an attractive force on the electron cloud of the other ion, which has accepted the electrons from the aluminum (or other) positive ion.

  9. Hydride - Wikipedia

    en.wikipedia.org/wiki/Hydride

    Ionic hydrides are used as bases and, occasionally, as reducing reagents in organic synthesis. [12] C 6 H 5 C(O)CH 3 + KH → C 6 H 5 C(O)CH 2 K + H 2. Typical solvents for such reactions are ethers. Water and other protic solvents cannot serve as a medium for ionic hydrides because the hydride ion is a stronger base than hydroxide and most ...