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  2. Bond valence method - Wikipedia

    en.wikipedia.org/wiki/Bond_valence_method

    If the structure of a compound is known, the empirical bond valence - bond length correlation of Eq. 2 can be used to estimate the bond valences from their observed bond lengths. Eq. 1 can then be used to check that the structure is chemically valid; any deviation between the atomic valence and the bond valence sum needs to be accounted for.

  3. Chirgwin–Coulson weights - Wikipedia

    en.wikipedia.org/wiki/Chirgwin–Coulson_weights

    In valence bond theory, however, the generated structures are not necessarily orthogonal with each other, and oftentimes have substantial overlap between the two structures. As such, when considering non-orthogonal constituent orbitals (i.e. orbitals with non-zero overlap) the non-diagonal terms in the overlap matrix would be non-zero, and must ...

  4. AKLT model - Wikipedia

    en.wikipedia.org/wiki/AKLT_model

    The main insight of the AKLT paper was that this construction could be generalized to obtain exactly solvable models for spin sizes other than 1/2. Just as one end of a valence bond is a spin 1/2, the ends of two valence bonds can be combined into a spin 1, three into a spin 3/2, etc.

  5. Abegg's rule - Wikipedia

    en.wikipedia.org/wiki/Abegg's_rule

    Abegg's rule is sometimes referred to as "Abegg’s law of valence and countervalence". In general, for a given chemical element (as sulfur) Abegg's rule states that the sum of the absolute value of its negative valence (such as −2 for sulfur in H 2 S and its positive valence of maximum value (as +6 for sulfur in H 2 SO 4) is often equal to 8.

  6. Valence (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Valence_(chemistry)

    In some molecules, there is a difference between valence and oxidation state for a given atom. For example, in disulfur decafluoride molecule S 2 F 10, each sulfur atom has 6 valence bonds (5 single bonds with fluorine atoms and 1 single bond with the other sulfur atom). Thus, each sulfur atom is hexavalent or has valence 6, but has oxidation ...

  7. Valence bond theory - Wikipedia

    en.wikipedia.org/wiki/Valence_bond_theory

    A valence bond structure resembles a Lewis structure, but when a molecule cannot be fully represented by a single Lewis structure, multiple valence bond structures are used. Each of these VB structures represents a specific Lewis structure. This combination of valence bond structures is the main point of resonance theory.

  8. Pauling's rules - Wikipedia

    en.wikipedia.org/wiki/Pauling's_rules

    For a given cation, Pauling defined [2] the electrostatic bond strength to each coordinated anion as =, where z is the cation charge and ν is the cation coordination number. A stable ionic structure is arranged to preserve local electroneutrality , so that the sum of the strengths of the electrostatic bonds to an anion equals the charge on ...

  9. Molecular orbital theory - Wikipedia

    en.wikipedia.org/wiki/Molecular_orbital_theory

    In this molecule, 24 of the 30 total valence bonding electrons – 24 coming from carbon atoms and 6 coming from hydrogen atoms – are located in 12 σ (sigma) bonding orbitals, which are located mostly between pairs of atoms (C–C or C–H), similarly to the electrons in the valence bond description.