Ultraviolet and Visible Absorption

Extinction coefficients e were measured for the gaseous [1 to 3] and the liquid state [4]. 

In the liquid state, the molar extinction coefficient was measured [4] at 77 K  

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Determination of purity. The ultraviolet and visible absorption is often a fairly intensive property thus e values of high intensity bands may be of the order of 10 -10 . In infrared spectra e values rarely exceed 10 . It is therefore often easy to pick out a characteristic band of a substance present in small concentration in admixture with other materials. Thus small amounts of aromatic compounds can be detected in hexane or in cyclohexane. 

A. Electronic (Ultraviolet and Visible) Absorption Spectra The electronic absorption spectra of heterocyclic molecules have their origins in the transitions of electrons between different molecular orbitals. In general, the more these orbitals are spread out in space, the closer together are their energy levels and the longer the wavelengths... 

Chase, A. M., and Brigham, E. H. (1951). The ultraviolet and visible absorption spectra of Cypridina luciferin solutions. J. Biol. Chem. 190 529-536. 

W.A. Schroeder et al, Ultraviolet and Visible Absorption Spectra in Ethyl Alcohol. 

Salfeld JC (1972) Ultraviolet and visible absorption spectra of humic systems. In Humic Substances (eds Povoledo D, Golterman HL), Center for Agriculture Publications and Documentation, Wageningen, The Netherlands, p. 269-280... 

Structural elements causing near ultraviolet and visible absorption and colour are called chromophores. There kinds of chromophores exist. 

British Pharmacopoeia, Appendix II, B, Ultraviolet and Visible Absorption Spectrophotometry, 2001. 

CA 49,7391(1955)(Explosive combustion of hydrocarbons — comparative investigation and study of continuous spectra) llJH.M.Hershen-son, "Ultraviolet and Visible Absorption Spectra , Index for 25 years — 1930 to 1954, Academic Press, NY(1956) I2)A.Gillam ... 

B-61MI21400 H. M. Hershenson in Ultraviolet and Visible Absorption Spectra, Indexes for... 

CA 43, 8l38-9( 1949)(Chromatographic investigation of proplnts using various stabilizers, among them Centr 2) 5)W. A.Schroeder er al, AnalChem 23, 1740-7(1951) CA 46, 5434(1952) (Detn of ultraviolet and visible absorption spectra of several stabilizers, among them Centr 2, in ethanol) 6)F.Pristera, AnalChem 25, 844... 

The ultraviolet and visible absorption spectra of single atoms consist of a number of sharp lines, which correspond to the promotion of an electron from one orbital to another. Each atomic orbital has a well-defined energy, and there-... 

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