What does chromophore mean?
A chromophore is the portion of a molecule that gives it colour. It works by absorbing particular wavelengths of visible light; the wavelengths not absorbed are reflected or transmitted, and these are what we perceive as the substance's colour. Most chromophores contain chains of alternating single and double bonds — conjugated systems — whose electrons are easily excited by light energy. Familiar examples include the azo groups of many synthetic dyes, the extended ring system of chlorophyll that makes plants green, and retinal in the eye's photoreceptors. The word belongs chiefly to the vocabulary of chemistry, dyeing, and molecular biology, where scientists speak of shifting, extending, or modifying a chromophore to tune a compound's colour. Related terms include auxochrome, a neighbouring group that intensifies or alters a chromophore's effect. Though technical rather than conversational, chromophore neatly captures a central idea: colour is not a property spread evenly through matter, but the work of small, precise arrangements of atoms.
nounA chromophore is the part of a molecule responsible for its colour, typically a group of atoms whose electrons absorb certain wavelengths of visible light. The term is used chiefly in chemistry and biochemistry.
- The specific part of a molecule — usually an unsaturated or conjugated atomic group — responsible for its colour by absorbing visible light.
"The azo group acts as the chromophore, giving the dye its intense red colour."
"Chemists modified the chromophore to shift the dye's absorption toward longer wavelengths."
"In retinal, the chromophore changes shape when struck by light, triggering the cascade of signals behind vision."
Regular English plural, formed by adding -s.
"Different chromophores within the same pigment can produce layered shades of colour."
The vivid blues of denim and the pinks of flowers both come down to one thing: a tiny cluster of atoms called a chromophore, quietly absorbing the light your eyes never see.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of chromophore
Chromophore derives from German Chromophor, coined in the late nineteenth century during early research into the chemistry of dyes, from Greek roots: chrōma meaning 'colour' and phoros meaning 'bearing' or 'carrying'. The term entered English scientific usage shortly after its German coinage as theories of dye structure developed. It shares its Greek roots with words such as chromatic, monochrome, and chromatography, all built on chrōma.
Related word forms
How chromophore is actually used
Chromophore is a technical term used mainly in chemistry, physics, dyeing, and molecular biology; it rarely appears in everyday speech. It is countable and takes standard plural forms. In scientific writing it often appears alongside 'auxochrome', a group that modifies a chromophore's colour.
Easily confused with chromophore
A chromosome is a thread-like structure of DNA in cells, whereas a chromophore is the colour-producing part of a chemical molecule.
A chromatophore is a pigment-containing cell in animals such as fish and cephalopods, while a chromophore is a molecular group that absorbs light and produces colour.