A chromophore is a molecule or ion that absorbs light of a particular wavelength, giving it the ability to selectively absorb certain colors. The word chromophore comes from the Greek words “chroma,” meaning color, and “phoros,” meaning bearing. Chromophores are found in many biological molecules, such as hemoglobin, which gives blood its red color. They are also found in many dyes and pigments used in paints, inks, and plastics.
The vast majority of organic chromophores contain conjugated double bonds – that is, alternating single and double bonds between carbon atoms. When light strikes this type of bond, it can cause an electron to jump from one bonding orbital to another (a process called photoexcitation). This jump puts energy into the molecule, which can then be released as heat, fluorescence, or other types of light emission.
The specific wavelength of light that a chromophore absorbs depends on the particular arrangement of its atoms. For example, the most common type of conjugated double bond – one where the alternating single and double bonds are between carbon atoms – will absorb light with a wavelength somewhere in the visible range (400-700 nm). But if there are other atoms present in the molecule – such as nitrogen or oxygen – they can modify this absorption spectrum. And if the Double bond is not between two carbon atoms but rather between a carbon atom and some other element like sulfur or phosphorus ,the absorption wavelength will be shifted to lower energies (longer wavelengths). In general, though, organic chromophores tend to absorb blue or violet light more strongly than red or infraredlight.
Chromophores play an important role in many biological processes. For example, they are responsible for absorbing sunlight so that plants can convert it into chemical energy via photosynthesis. In animals ,chromophores helps regulate body temperature by absorbing ultraviolet radiation from sunlight and converting it into heat .They also play a role in vision by absorbing different colors of light and sending corresponding signals to our brains . Finally ,chromophores are used extensively in research laboratories as tools for studying biomolecules . By attaching fluorescent tags onto specific proteins or DNA sequences ,scientists can track their movements inside cells using special microscopes .