refractivity


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re·frac·tiv·i·ty

(rē'frak-tiv'i-tē),
Refractive power.
Synonym(s): refringency

re·frac·tiv·i·ty

(rē'frak-tiv'i-tē)
Refractive power.

refractivity

(rē″frăk-tĭv′ĭ-tē)
The quality of being refractive; the ability to refract.

dispersion

Phenomenon of the change in velocity of propagation of radiation in a medium, as a function of its frequency, which causes a separation of the monochromatic components of a complex radiation. All optical media cause dispersion by virtue of their variation of refractive index with wavelengths. Dispersion is specified by the difference in the refractive index of the medium for two wavelengths. The difference between the blue F (486.1 nm) and the red C (656.3 nm) spectral lines is called the mean dispersion, i.e. nFnC. Dispersion is usually represented by its dispersive power ω or relative dispersion which is equal to the mean dispersion divided by the excess refractive index of the helium d (587.6 nm) spectral line (nd − 1), often called the refractivity of the material,
ω = nFnC/nd − 1
The reciprocal of the dispersive power is called the Abbé's number or constringence (Fig. D8). See aberration longitudinal chromatic; achromatic axis; Fraunhoffer's lines; achromatic prism.
Fig. D8 Dispersion of a white beam of light by a prismenlarge picture
Fig. D8 Dispersion of a white beam of light by a prism
References in periodicals archive ?
Because error is present in both refractivity and osmolality measurements, Deming regression was used to estimate the [alpha] and [beta] values from Eq (2)
ow], CLogP, (octanol/water partition coefficient calculated by Hansch's method), and MLogP (octanol/water partition coefficient calculated by Moriguchi's method)], size [MW (molecular weight) and MgVol (molar volume calculated by McGowan's method)], polarizability [CMR, (molar refractivity calculated by Hansch's method), AMR (calculated by Ghose and Crippen's method), and PolarizG (polarizability calculated by Glen's method)], and constitutional descriptors [TPSA (topologic polar surface area), HBA (number of hydrogen-bond acceptors), nCL (number of chlorines), and nBR (number of bromines)] (Table 3) (Abraham and McGowan 1987; Ghose and Crippen 1987; Glen 1994; Leo et al.
CPE was focal, with cell rounding and a refractivity that was soon followed by cell detachment, and CPE quickly spread to involve the entire cell monolayer (Figure 1).
While molar refractivity (MR) improves on 5, it also includes implicit information on the polarizability of the molecule.
For example, there are now PC programs available to compute molar refractivity, molar volume, parachor, index of refraction, surface tension, density, dielectric constant, polarizability, dipole moment, acid constant, octanol/water partition coefficient, and other physicochemical properties directly from the SMILES string or molecular structure graph.