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  2. Topological index - Wikipedia

    en.wikipedia.org/wiki/Topological_index

    In the fields of chemical graph theory, molecular topology, and mathematical chemistry, a topological index, also known as a connectivity index, is a type of a molecular descriptor that is calculated based on the molecular graph of a chemical compound. [1]

  3. Molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Molecular_geometry

    Molecules, by definition, are most often held together with covalent bonds involving single, double, and/or triple bonds, where a "bond" is a shared pair of electrons (the other method of bonding between atoms is called ionic bonding and involves a positive cation and a negative anion).

  4. Tetrahedral molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Tetrahedral_molecular_geometry

    In a tetrahedral molecular geometry, a central atom is located at the center with four substituents that are located at the corners of a tetrahedron.The bond angles are arccos(− ⁠ 1 / 3 ⁠) = 109.4712206...° ≈ 109.5° when all four substituents are the same, as in methane (CH 4) [1] [2] as well as its heavier analogues.

  5. Randić's molecular connectivity index - Wikipedia

    en.wikipedia.org/wiki/Randić's_molecular...

    The Randić index, also known as the connectivity index, of a graph is the sum of bond contributions / / where and are the degrees of the vertices making bond i ~ j. History [ edit ]

  6. Coordination cage - Wikipedia

    en.wikipedia.org/wiki/Coordination_cage

    Coordinate bonds are useful in such supramolecular self-assembly because of their versatile geometries. [1] However, there is controversy over calling coordinate bonds noncovalent, as they are typically strong bonds and have covalent character. [2] The combination of a coordination cage and a guest is a type of inclusion compound. Coordination ...

  7. Chemical structure - Wikipedia

    en.wikipedia.org/wiki/Chemical_structure

    Phosphorus pentoxide chemical structure in 2D. A chemical structure of a molecule is a spatial arrangement of its atoms and their chemical bonds. Its determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid.

  8. Reaction coordinate - Wikipedia

    en.wikipedia.org/wiki/Reaction_coordinate

    In chemistry, a reaction coordinate [1] is an abstract one-dimensional coordinate chosen to represent progress along a reaction pathway. Where possible it is usually a geometric parameter that changes during the conversion of one or more molecular entities , such as bond length or bond angle .

  9. Coordinate covalent bond - Wikipedia

    en.wikipedia.org/wiki/Coordinate_covalent_bond

    In coordination chemistry, a coordinate covalent bond, [1] also known as a dative bond, [2] dipolar bond, [1] or coordinate bond [3] is a kind of two-center, two-electron covalent bond in which the two electrons derive from the same atom. The bonding of metal ions to ligands involves this kind of interaction. [4]