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A UV-Vis spectrophotometer is an analytical instrument that measures the amount of ultraviolet (UV) and visible light that is absorbed by a sample. It is a widely used technique in chemistry, biochemistry, and other fields, to identify and quantify compounds in a variety of samples.
Ultraviolet-visible (UV-vis) spectroscopy involves energy levels that excite electronic transitions. Absorption of UV-vis light excites molecules that are in ground-states to their excited-states. [5] Visible region 400–700 nm spectrophotometry is used extensively in colorimetry science. It is a known fact that it operates best at the range ...
Figure 1: Simplified schemes of the Variable UV-Vis detector compared to PhotoDiode Array detector. In the Variable UV-Vis the entire optical bench is located before the flow cell whereas in the diode array the flow rate is positioned before the main optical bench. A schematic of the optical systems is shown in Figure 1.
If the instrument is designed to measure the spectrum on an absolute scale rather than a relative one, then it is typically called a spectrophotometer. The majority of spectrophotometers are used in spectral regions near the visible spectrum. A spectrometer that is calibrated for measurement of the incident optical power is called a ...
An XPS spectrometer. A spectrometer (/ s p ɛ k ˈ t r ɒ m ɪ t ər /) is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are somehow mixed.
In ultraviolet-visible spectroscopy or spectroscopy in general a 1 cm pathlength cuvette is used to measure samples. The cuvette is filled with sample, light is passed through the sample and intensity readings are taken. The slope spectroscopy technique can be applied using the same methods as in absorption spectroscopy.
It is the link between the electrochemistry and the UV-Vis absorption spectroscopy. [3] Devices to conduct the radiation beam: lenses, mirrors and/or optical fibers. The last ones conduct electromagnetic radiation over great distances with hardly any losses.
UV–vis spectroscopy sees only chromophores, so other molecules must be prepared for analysis by chemical addition of a chromophore such as anthracene. Two methods are reported: the octant rule and the exciton chirality method. [1] The octant rule was introduced in 1961 by William Moffitt, R. B. Woodward, A. Moscowitz, William Klyne and Carl ...