Absorptivity
Encyclopedia
The term absorptivity has two meanings:
- In chemistry, it usually refers to Molar absorptivityMolar absorptivityThe molar absorption coefficient, molar extinction coefficient, or molar absorptivity, is a measurement of how strongly a chemical species absorbs light at a given wavelength...
: the constant
used in the Beer-Lambert lawBeer-Lambert lawIn optics, the Beer–Lambert law, also known as Beer's law or the Lambert–Beer law or the Beer–Lambert–Bouguer law relates the absorption of light to the properties of the material through which the light is travelling.-Equations:The law states that there is a logarithmic dependence between the...
,
, where 
is the absorbance, 
is the concentration of the solution, and 
is the path length. - In physics, the word is used interchangeably with absorbance : the fraction of radiation absorbed at a given wavelength.