Search results
Results from the WOW.Com Content Network
In chemistry, delocalized electrons are electrons in a molecule, ion or solid metal that are not associated with a single atom or a covalent bond. [1] The term delocalization is general and can have slightly different meanings in different fields: In organic chemistry, it refers to resonance in conjugated systems and aromatic compounds.
Standard ab initio quantum chemistry methods lead to delocalized orbitals that, in general, extend over an entire molecule and have the symmetry of the molecule. Localized orbitals may then be found as linear combinations of the delocalized orbitals, given by an appropriate unitary transformation.
Delocalized molecular wavefunctions over the entire volume: Transition between localized sites via tunnelling (electrons) or overcoming potential barriers (ions) Inter-site distance: Bond length (less than 1 nm) Typically more than 1 nm Mean free path: Larger than the inter-site distance: Inter-site distance Mobility
The presence of such bands allows electrons in metals to behave as if they were free or delocalized electrons. These electrons are not associated with specific atoms, so when an electric field is applied, they are free to move like a gas (called Fermi gas) [137] through the material much like free electrons.
Cinnamaldehyde is a naturally-occurring compound that has a conjugated system penta-1,3-diene is a molecule with a conjugated system Diazomethane conjugated pi-system. In theoretical chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in a molecule, which in general lowers the overall energy of the molecule and increases stability.
Benzene, the most widely recognized aromatic compound with six delocalized π-electrons (4n + 2, for n = 1). In organic chemistry, Hückel's rule predicts that a planar ring molecule will have aromatic properties if it has 4n + 2 π-electrons, where n is a non-negative integer.
In reality, the dangling bond unbound orbital is better described by having more than half of the dangling bond wave function localized on the silicon nucleus, [2] with delocalized electron density around the three bonding orbitals, comparable to a p-orbital with more electron density localized on the silicon nucleus. The three remaining bonds ...
The electron density of these two bonding electrons in the region between the two atoms increases from the density of two non-interacting H atoms. Two p-orbitals forming a pi-bond. A double bond has two shared pairs of electrons, one in a sigma bond and one in a pi bond with electron density concentrated on two opposite sides of the ...