Refractive dispersion

Sumer, K.M. and Thompson, A.R. Refraction, dispersion, and densities of benzene, toluene, and xylene mixtures. J. Chem. Eng. Data, 13(l) 30-34,1968. 

Measurements are made of the properties of boiling point (at an appropriate pressure), density, refractive index, refractive dispersion (for appropriate wave lengths), viscosity, critical solution temperature in one or more appropriate solvents, infrared absorption (normally in the range 2 to 15 microns), ultraviolet absorption (normally in the range 0.2 to 0.4 micron or 2000 to 4000 A.), elemental composition, and average molecular weight. 

Reinkober studied the reflexion spectra for ultra-red rays. According to J. H. Gladstone and W. H. Perkin,12 the molecular refraction, dispersion, and magnetic rotation of the ammonium halides are ... 

The wave theory of light, which operates with continuous spatial functions, has worked well in the representation of purely optical phenomena and will probably never be replaced by another theory. It should be kept in mind, however, that the optical observations refer to time averages rather than instantaneous values. In spite of the complete experimental confirmation of the theory as applied to diffraction, reflection, refraction, dispersion, etc., it is still conceivable that the theory of light which operates with continuous spatial functions may lead to contradictions with experience when it is applied to the phenomena of emission and transformation of light. 

The term dispersion in dispersion forces comes from an analogy to the refraction (dispersion) of light due to induced dipole interactions. Since London s induced dipole-induced dipole interactions resemble this, the term Dispersion Forces was coined which is unfortunate in that these dispersion forces act against the dispersion of colloidal particles. 

Table 19 shows a few examples of R s calculated in three ways (A) by fitting Rc, RB, Rv and RG- from the literature to the equation RX = R0o + (constant )A-2, (B) as 0-95UD, and (C) by summation of bond polarizations from Table 18. The Rx s under (C) are close to those under (A) and offer some justification for using Table 18 with molecules for which refraction-dispersion data are not known.

ASTM D 1218-96. Standard test method for refractive index and refractive dispersion of hydrocarbon liquids. 

Gladstone JH, Dale TP (1863) Researches on the refraction, dispersion, and sensitiveness of... 

Material Useful spectral range [ptn] 1 Refractive Dispersion index n d/dx [nm l] ... 

ASTM Test Method D1218, Refractive Index and Refractive Dispersion of Hydrocarbon Liquids, is designed to use the Bausch Lomb Precision Refractometer. This model is no longer manufactured. ASTM Test Method D1747, Refractive Index of Viscous Materials, uses the Abbe t3T>e (Valentine) refractometer, which is no longer made. In both cases, other refractometers are available, but no cooperative work has been conducted to verify equivalence. There are also limitations on the availability of thermometers with suitable range and accuracy that will fit the instruments. ASTM Subcommittee D02.04.0D plans cooperative testing of modem commercial refractometers to develop precision data, but data are not yet available. 

D1218 Test Method for Refiactive Index and Refractive Dispersion of Hydrocarbon Liquids ... 

Refractive index and refractive dispersion are fundamental physical properties which can be u in conjunction with other properties to characterize pure hydrocarbons and their mixtures. 

Refractive index is measured by a standard method. " It covers transparent and hght colored liquids having a refractive index in the range from 1.33 to 1.50. The refractive index is the ratio of hght velocity of a specified wavelength in air to its velocity in the substance under evaluation. The refractive dispersion is the difference between refractive indices for... 

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