Ultraviolet-Visible-Near-Infrared Spectrophotometer

In general, this instrument is used to determine the absorption spectrum of a substance by irradiating it with UV to near-infrared light (200 to 2500 nm) while it is dissolved in a solvent and measuring the amount of light transmitted through it. Electrons in atoms and molecules absorb light of the energy specific to the substance and change from the ground state to the excited state energy level. From the wavelength of this absorbed light, the electronic state of the substance can be determined. Especially in transition metal complexes, characteristic absorption bands involving d- and f-electrons appear and are often measured. Since there is a proportional relationship between the concentration of a substance and its absorbance, it can also be used for reaction rate analysis.