| 释义 |
Raman Chem. and Physics.|ˈrɑːmən|
Also (rare) raman.
The name of Sir Chandrasekhara Venkata Raman (1888–1970), Indian physicist, used attrib. and in Comb. with reference to the Raman effect he discovered, as Raman band, Raman line, Raman shift (so Raman-shifted adj.), Raman spectrometer, Raman spectroscopy, etc.; Raman-active a., capable of giving rise to Raman scattering; Raman effect, scattering, the scattering of light by a substance with a change in the frequency of the light by an amount which is characteristic of the scattering substance and represents a change in the vibrational, rotational, or electronic energy of the substance; occas. with ellipsis of effect; Raman spectrum, a spectrum of scattered light showing additional bands produced by the Raman effect.
1928Nature 29 Sept. 477/2 (heading) The Raman effect in crystals. 1929Ibid. 24 Aug. 301/1 The Raman spectra for various liquids. 1937Jrnl. Amer. Chem. Soc. LIX. 1139/1 It is generally admitted that the 3654 cm—1 Raman band of water vapor corresponds to the symmetric..vibration. 1945G. Herzberg Infrared & Raman Spectra of Polyatomic Molecules iii. 243 All three vibrations of non-linear symmetric..XY2 are Raman active as well as infrared active. 1947Nature 11 Jan. 60/2 The principal feature noticeable in the spectra is the appearance of a whole series of sharply defined Raman lines. 1947Thorpe's Dict. Appl. Chem. (ed. 4) VIII. 190/1 Fundamental frequencies will be active in Raman scattering only when the mode of vibration of the molecule associated with that fundamental frequency causes an equiperiodic variation in the polarisibility of the molecule. 1950W. J. Moore Physical Chem. xi. 332 Since the Raman spectra are studied with light sources in the visible or ultra⁓violet, they provide a convenient means of obtaining the same sort of information about molecular structure as is given by the infrared spectra. In many cases, the two methods supplement each other, since vibrations and rotations that are not observable in the infrared..may be active in the Raman. 1958Oxf. Univ. Gaz. 23 Apr. 881 Application of raman spectra to chemical problems. 1962Times 9 Mar. 2/6 (Advt.), The successful applicant will work in one of the following fields:..ultra-violet, infra-red and Raman spectroscopy of aromatic, N-heterocyclic and tautomerizable substances. 1966D. H. Whiffen Spectroscopy ix. 110 The Raman lines are always extremely weak with respect to the incident light intensity. 1967L. A. Woodward in H. A. Szymanski Raman Spectroscopy I. i. 16 In practice, the pure rotational Raman shifts are small..and it is necessary to use a spectrograph of high dispersion and resolving power. 1970Gilson & Hendra Laser Raman Spectroscopy ii. 21 In the basic Raman spectrometer, the sample under examination is subjected to irradiation from a suitable monochromatic source, and the Raman spectrum is observed by use of a system comprising a monochromator, detector, and recorder. 1974Nature 8 Mar. 124/1 Raman-shifted backscatter of laser radar radiation from atmospheric constituents in the troposphere has been reported. 1976Jrnl. Chem. Soc. Dalton Trans. 1148/2 Five of the six Raman-active vibrations of the two octahedral anions..were clearly observed. 1978P. W. Atkins Physical Chem. xvii. 563 The molecule is active in the Raman because the end-over-end rotation modulates its polarizability as viewed by a stationary observer. |