In the case of phenol and benzene, a circle inside a hexagon shows the de-localized nature of the compound.

When absorbed by an AgX crystal, photons cause electrons to be promoted to a conduction band ( de-localized electron orbital with higher energy than a valence band ) which can be attracted by a sensitivity speck, which is a shallow electron trap, which may be a crystalline defect or a cluster of silver sulfide, gold, other trace elements ( dopant ), or combination thereof, and then combined with an interstitial silver ion to form silver metal speck.

Those ions are surrounded by de-localized electrons, which are responsible for the conductivity.

These assumptions have been challenged by later scholarship that have demonstrated that individuals generally participate in various speech communities simultaneously and at different times in their lives each of which has a different norms that they tend to share only partially, communities may be de-localized and unbounded rather than local, and they often comprise different sub-communities with differing speech norms.

In 1964, Hückel method calculations ( using a simple linear combination of atomic orbitals ( LCAO ) method for the determination of electron energies of molecular orbitals of π electrons in conjugated hydrocarbon systems ) of molecules ranging in complexity from butadiene and benzene to ovalene, were generated on computers at Berkeley and Oxford.

All are coloured to the human eye, due to extensive systems of conjugated double bonds.

Various specialized properties of molecular crystals and organic polymers with conjugated systems are of interest depending on applications, e. g. thermo-mechanical and electro-mechanical such as piezoelectricity, electrical conductivity ( see conductive polymers and organic semiconductors ), and electro-optical ( e. g. non-linear optics ) properties.

When this light encounters a pigment, parts of the spectrum are absorbed by the chemical bonds of conjugated systems and other components of the pigment.

Thus porphyrin macrocycles are highly conjugated systems.

Many pigments make use of conjugated electron systems, such as the long conjugated hydrocarbon chain in beta-carotene, resulting in a strong orange color.

Conjugated systems of fewer than eight conjugated double bonds absorb only in the ultraviolet region and are colorless to the human eye.

Porphyrins have conjugated molecular ring systems ( macrocycles ) that appear in many enzymes of biological systems.

As the number of double bonds increases, electrons associated with conjugated systems have more room to move, and require less energy to change states.

Classically, delocalized electrons can be found in conjugated systems and mesoionic compounds.

As an approximation, the conjugated backbone can be considered as a real-world example of the “ electron-in-a-box ” solution to the Schrödinger equation ; however, the development of refined models to accurately predict absorption and fluorescence spectra of well-defined oligo ( thiophene ) systems is ongoing.

* Foiled carbenes derive their stability from proximity of a double bond ( i. e. their ability to form conjugated systems ).

Aromatic compounds, also known as arenes or aromatics, are chemical compounds that contain conjugated planar ring systems with delocalised pi electron clouds instead of discrete alternating single and double bonds.

Simple aromatic rings are aromatic organic compounds ( also known as arenes or aromatics ) that consist only of conjugated planar ring systems with delocalized pi electron clouds instead of discrete alternating single and double bonds.

In systems with a very large number of states like macromolecules and large conjugated systems the separate energy levels can't always be distinguished in an absorption spectrum.

For charge-transfer complexes and conjugated systems the band width is determined by a variety of factors.

In principle any unsaturated molecule can form a radical anion, but the antibonding orbitals are only energetically accessible in more extensive conjugated systems.

Chromophores almost always arise in one of two forms: conjugated pi systems ( also known as resonating systems ) and metal complexes.

In the conjugated chromophores, the electrons jump between energy levels that are extended pi orbitals, created by a series of alternating single and double bonds, often in aromatic systems.

Woodward-Fieser rules can be used to approximate ultraviolet-visible maximum absorption wavelength in organic compounds with conjugated pi-bond systems.

Polymerization of conjugated dienes such as buta-1, 3-diene or isoprene ( 2-methylbuta-1, 3-diene ) results in largely 1, 4-addition with possibly some 1, 2-addition of the diene monomer to a growing polymer chain.

Fatty acids such as conjugated linoleic acid, catalpic acid, eleostearic acid and punicic acid, in addition to providing energy, represent potent immune modulatory molecules.

Before the specific dangers of conjugated equine estrogens were well understood, standard therapy was 0. 625 mg / day of conjugated equine estrogens ( such as Premarin ).

The main difference from other ancient Indo-European languages, such as Latin, is that verbs can be conjugated in only two tenses ( vs. the six " tenses " – really tense / aspect combinations – of Latin ), and have no synthetic passive voice ( although it did still exist in Gothic ).

*** synthetic rubbers-synthetic elastomers made of any one or more of several petrochemical ( usually ) monomers such as 1, 3-butadiene, styrene, isobutylene, isoprene, chloroprene ; elastomeric polymers are often made with a high percentage of conjugated diene monomers such as 1, 3-butadiene, isoprene, or chloroprene

UV / Vis spectroscopy is routinely used in analytical chemistry for the quantitative determination of different analytes, such as transition metal ions, highly conjugated organic compounds, and biological macromolecules.

The Woodward-Fieser rules, for instance, are a set of empirical observations used to predict λ < sub > max </ sub >, the wavelength of the most intense UV / Vis absorption, for conjugated organic compounds such as dienes and ketones.

Therefore, only é and è are normally contrasted, typically in words ending in-ché, such as perché (" why / because "); in the conjugated copula è (" is "); in ambiguous monosyllables such as né (' neither ') vs. ne (' of it ') and sé (' itself ') vs. se (' if '); and some verb forms, e. g. poté (" he / she / it could " ( past tense )).

Focal neurological deficits may also occur, such as abducens nerve palsy and vertical gaze palsy ( Parinaud syndrome due to compression of the quadrigeminal plate, where the neural centers coordinating the conjugated vertical eye movement are located ).

Estradiol is conjugated in the liver by sulfate and glucuronide formation and, as such, excreted via the kidneys.

Since 9, 10-dihydroanthracene in essence preserves two " benzene " rings ( a total of 6 conjugated pi bonds ), whereas the 1, 4-isomer preserves only one and a half such rings ( a total of 5 pi bonds ); the latter is not the thermodynamically favorable product.

Normally carbon-carbon double bonds which are not conjugated or only conjugated with only one or two other carbon-carbon double bonds have high enough energy that they absorb in the ultraviolet region of a spectrum, but the absorption energy state of polyenes with numerous conjugated double bonds can be lowered such that they enter the visible region of the spectrum, resulting in compounds which are coloured.

The conjugated verb has other spins that are worth noting, such as: " Hishtalem " meaning " it was worth it " or " Shulam " as " it was paid for " or " Meshulam " as in " paid in advance.

These problems can be alleviated by using alternative electrode materials such as conjugated polymers which can undergo the Faradaic reactions themselves, dramatically reducing electrolysis.

In extended viologens conjugated oligomers such as based on aryl, ethylene, and thiophene units are inserted between the pyridine units.

Cinnamaldehyde, a type of natural phenol | phenolic compound with a conjugated system

A quinone is a class of organic compounds that are formally " derived from aromatic compounds as benzene or naphthalene by conversion of an even number of – CH = groups into – C (= O )– groups with any necessary rearrangement of double bonds ," resulting in " a fully conjugated cyclic dione structure.

However, none of the larger annulenes are as stable as benzene, as their reactivity more closely resembles a conjugated polyene than an aromatic hydrocarbon.