auxochrome

n. group of atoms which intensify color (Chemistry)

Auxochrome - this is a group of atoms attached to a chromophore which modifies the ability of that chromophore to absorb light. Example: -OH , - NH2 , Aldehydes Attached group which enables the attached of the coloured molecule Add a chemical group to the molecule of the dye so as to enable its attachment to the tissue structures while without changing its colour or stability. If these groups are in direct conjugation with the pi-system of chromophore, they may increase the wavelength at which the light is absorbed and as a result intensify the absorption. A feature of these auxochromes is the presence of at least one lone pair of electrons which can be viewed as extending the cojugated system by resonance.
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n. auxochrome, group of atoms which intensify color (Chemistry)

n. auxochrome, group of atoms which intensify color (Chemistry)

Compare with chromophore .A group or substructure in a molecule that influences the intensity of absorption of the molecule.