When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Sigma bond - Wikipedia

    en.wikipedia.org/wiki/Sigma_bond

    According to the sigma bond rule, the number of sigma bonds in a molecule is equivalent to the number of atoms plus the number of rings minus one. N σ = N atoms + N rings − 1. This rule is a special-case application of the Euler characteristic of the graph which represents the molecule. A molecule with no rings can be represented as a tree ...

  3. Localized molecular orbitals - Wikipedia

    en.wikipedia.org/wiki/Localized_molecular_orbitals

    In the water molecule for example, ab initio calculations show bonding character primarily in two molecular orbitals, each with electron density equally distributed among the two O-H bonds. The localized orbital corresponding to one O-H bond is the sum of these two delocalized orbitals, and the localized orbital for the other O-H bond is their ...

  4. Single bond - Wikipedia

    en.wikipedia.org/wiki/Single_bond

    Usually, a single bond is a sigma bond. An exception is the bond in diboron, which is a pi bond. In contrast, the double bond consists of one sigma bond and one pi bond, and a triple bond consists of one sigma bond and two pi bonds (Moore, Stanitski, and Jurs 396). The number of component bonds is what determines the strength disparity.

  5. Carbon–carbon bond - Wikipedia

    en.wikipedia.org/wiki/Carbon–carbon_bond

    The carbon–carbon single bond is a sigma bond and is formed between one hybridized orbital from each of the carbon atoms. In ethane, the orbitals are sp 3-hybridized orbitals, but single bonds formed between carbon atoms with other hybridizations do occur (e.g. sp 2 to sp 2). In fact, the carbon atoms in the single bond need not be of the ...

  6. Hyperconjugation - Wikipedia

    en.wikipedia.org/wiki/Hyperconjugation

    Hyperconjugation affects several properties. [6] [10]Bond length: Hyperconjugation is suggested as a key factor in shortening of sigma bondsbonds). For example, the single C–C bonds in 1,3-butadiene and propyne are approximately 1.46 Å in length, much less than the value of around 1.54 Å found in saturated hydrocarbons.

  7. Inductive effect - Wikipedia

    en.wikipedia.org/wiki/Inductive_effect

    In Organic chemistry, the inductive effect in a molecule is a local change in the electron density due to electron-withdrawing or electron-donating groups elsewhere in the molecule, resulting in a permanent dipole in a bond. [1] It is present in a σ (sigma) bond, unlike the electromeric effect which is present in a π (pi) bond.

  8. Neighbouring group participation - Wikipedia

    en.wikipedia.org/wiki/Neighbouring_group...

    In organic chemistry, neighbouring group participation (NGP, also known as anchimeric assistance) has been defined by the International Union of Pure and Applied Chemistry (IUPAC) as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma or pi bond contained within the parent molecule but not conjugated with the reaction centre.

  9. Sigma complex - Wikipedia

    en.wikipedia.org/wiki/Sigma_complex

    This dihydrogen complex ([HFe(H 2)(dppe) 2] +) is an example of a sigma complex. See also: arenium ion In chemistry, a sigma complex or σ-complex usually refers to a family of coordination complexes where one or more ligands interact with the metal using the bonding electrons in a sigma bond.