A chromophore is part (or moiety) of a molecule responsible for its color. Look up moiety in Wiktionary, the free dictionary. ... In chemistry, a molecule is an aggregate of at least two atoms in a definite arrangement held together by special forces. ... Color is an important part of the visual arts. ...

When a molecule absorbs certain wavelengths of visible light and transmits or reflects others, the molecule has a color. A chromophore is a region in a molecule where the energy difference between two different molecular orbitals falls within the range of the visible spectrum. Visible light that hits the chromophore can thus be absorbed by exciting an electron from its ground state into an excited state. The visible spectrum (or sometimes optical spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ... In quantum chemistry, molecular orbitals are the statistical states electrons can have within molecules. ... The electron is a fundamental subatomic particle that carries an electric charge. ... In physics, the ground state of a quantum mechanical system is its lowest-energy state. ... It has been suggested that this article or section be merged with quantum state. ...

In biological molecules that serve to capture or detect light energy, the chromophore is the moiety that causes a conformational change of the molecule when hit by light. Look up moiety in Wiktionary, the free dictionary. ...

Chromophores almost always arise in one of two forms: conjugated pi systems and metal complexes. A chemically conjugated system, is a system of atoms covalently bonded with alternating single and double bonds (e. ... Synthesis of copper(II)-tetraphenylporphine, a metal complex, from tetraphenylporphine and copper(II) acetate monohydrate. ...

In the former, the energy levels that the electrons jump between are extended pi orbitals created by a series of alternating single and double bonds, often in aromatic systems. Common examples include retinal (used in the eye to detect light), various food colorings, fabric dyes (azo compounds), lycopene, β-carotene, and anthocyanins. Electron atomic and molecular orbitals, showing a Pi-bond at the bottom right of the picture In chemistry, pi bonds (Ï€ bonds) are bonds with a single nodal plane containing the line segment between the two atoms. ... A chemical bond is the physical phenomenon of chemical substances being held together by attraction of atoms to each other through sharing, as well as exchanging, of electrons or electrostatic forces. ... In chemistry, an aromatic molecule is one in which electrons are free to cycle around circular arrangements of atoms, which are alternately singly and doubly bonded to one another. ... In the vision system, retinal, technically called retinene1 or retinaldehyde, is a light-sensitive retinene molecule found in the photoreceptor cells of the retina. ... Food coloring spreading on a soap bubble A food coloring is any substance that is added to food to change its color. ... In chemistry, azo compounds generally have a molecular formula of the form R-N=N-R, in which R and R can be either aromatic or aliphatic. ... Please wikify (format) this article as suggested in the Guide to layout and the Manual of Style. ... Carotene is responsible for the orange colour of the carrots and many other fruits and vegetables. ... Anthocyanin is a pigment that reflects the red to blue range of the visible spectrum. ...

The metal complex chromophores arise from the splitting of d-orbitals by binding of a transition metal to ligands. Examples of such chromophores can be seen in chlorophyll (used by plants for photosynthesis), hemoglobin, hemocyanin, and colorful minerals such as malachite and amethyst. The d-block of the periodic table of elements consists of those periodic table groups that contain elements in which, in the atomic ground state, the highest-energy electron is in a d-orbital. ... In chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings: It commonly refers to any element in the d-block of the periodic table, including zinc, cadmium and mercury. ... In chemistry, a ligand is an atom, ion or functional group that is bonded to one or more central atoms or ions, usually metals generally through co-ordinate covalent bond. ... Chlorophyll is a green photosynthetic pigment found in plants, algae, and cyanobacteria. ... The leaf is the primary site of photosynthesis in plants. ... 3-dimensional structure of hemoglobin. ... Single Oxygenated Hemocyanin protein from Octopus Hemocyanins (also spelled haemocyanins) are respiratory proteins containing two copper atoms that reversibly bind a single oxygen molecule (O2). ... Minerals are natural compounds formed through geological processes. ... Malachite from the Democratic Republic of Congo Malachite is a carbonate mineral, copper(II) carbonate hydroxide Cu2CO3(OH)2. ... Amethyst (SiO2) is a violet or purple variety of quartz often used as an ornament. ...

A common motif in biochemistry is chromophores consisting of four pyrrole rings. These come in two types: Pyrrole, or pyrrol, is a heterocyclic aromatic organic compound, a five-membered ring with the formula C4H5N. Pyrroles are components of larger aromatic rings, including the porphyrins of heme, the chlorins and bacteriochlorins of chlorophyll, and the corrin ring of vitamin B12. ...

• the pyrroles form an open chain, no metal: phytochrome, phycobilin, bilirubin
• the pyrroles form a ring (porphyrin), with a metal in the center: hemoglobin, chlorophyll

Phytochrome is a photoreceptor, a pigment that plants use to detect light. ... Phycobilins are the chromophores of phycobiliproteins (photosynthetic pigments) found in cyanobacteria and in the chloroplasts of red algae, glaucophytes and some cryptomonads (though not in green algae and higher plants). ... Bilirubin is a yellow breakdown product of heme catabolism. ... A porphyrin is a heterocyclic macrocycle made from 3 pyrrole subunits and one pyrroline subunit, and linked on opposite sides through 4 methine bridges. ... 3-dimensional structure of hemoglobin. ... Chlorophyll is a green photosynthetic pigment found in plants, algae, and cyanobacteria. ...

External links

• Causes of Color: physical mechanisms by which color is generated.
• High Speed Nano-Sized Electronics May be Possible with Chromophores - Azonano.com