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Structural chemistry is a part of chemistry and deals with spatial structures of molecules (in the gaseous, liquid or solid state) and solids (with extended structures that cannot be subdivided into molecules). For structure elucidation [1] a range of different methods is used.
The term is used to describe a transient chemical species.As a general example, if a molecule exists in a particular conformation for a short lifetime, before adopting a lower energy conformation (structural arrangement), the former molecular structure is said to have 'high lability' (such as C 25, a 25-carbon fullerene spheroid).
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
A chemical bond is the association of atoms or ions to form molecules, crystals, and other structures. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds, or some combination of these effects.
A molecule that contains double or triple bonds separated by one single bond; e.g. the compound buta-1,3-diene, with the chemical structure H 2 C=CH−CH=CH 2, has conjugated double bonds. In such molecules, there is some delocalization of electrons in the pi orbitals between the carbon atoms linked by the single bond. [3]
Wavy single bonds represent unknown or unspecified stereochemistry or a mixture of isomers. For example, the adjacent diagram shows the fructose molecule with a wavy bond to the HOCH 2 - group at the left. In this case the two possible ring structures are in chemical equilibrium with each other and also with the open-chain structure.
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 ...
In chemistry, vinylene (also ethenylene or 1,2-ethenediyl) [1] is a divalent functional group (a part of a molecule) [2] with formula −CH=CH−; [3] namely, two carbons, each connected to the other by a double bond, to an hydrogen atom by a single bond, and to the rest of the molecule by another single bond.