Refraction molar

Here, k is a factor which converts to units (kcal/mol in this case where the distances are in A and the polarisabilities in A ). G, and Gj are constants chosen to reproduce the well depths for like-with-like interactions. The atomic polarisability values are obtained from an examination of appropriate molecular experimental data (such as measurements of molar refractivity). 

The molar refraction deduced for alkyl derivatives, compared to the value obtained by addition, to the experimental molar refraction of thiazole, of the classical (CH2) increment of Eisenlohr Rch 4.618 cm ), show specific exaltations which are typical for each position of the thiazole ring (Table 1-49). 

TABLE 1-49. SPECIHC EXALTATION OF MOLAR REFRACTION (IN PERCENTAGE OF THE CALCUL-LATED VALUE) (198, 199, 2l5)... 

From the atomic and group refractions in Table 5.19, the molar refraction is computed as follows ... 

Physical Methods of Examination. Physical methods used to examine coals can be divided into two classes which, in the one case, yield information of a stmctural nature such as the size of the aromatic nuclei, ie, methods such as x-ray diffraction, molar refraction, and calorific value as a function of composition and in the other case indicate the fraction of carbon present in aromatic form, ie, methods such as ir and nuclear magnetic resonance spectroscopies, and density as a function of composition. Some methods used and types of information obtained from them are (41) ... 

Parachor is the name (199) of a temperature-independent parameter to be used in calculating physical properties. Parachor is a function of Hquid density, vapor density, and surface tension, and can be estimated from stmctural information. Critical constants for about 100 organic substances have been correlated to a set of equations involving parachors and molar refraction (200). 

Theoretical and structural studies have been briefly reviewed as late as 1979 (79AHC(25)147) (discussed were the aromaticity, basicity, thermodynamic properties, molecular dimensions and tautomeric properties ) and also in the early 1960s (63ahC(2)365, 62hC(17)1, p. 117). Significant new data have not been added but refinements in the data have been recorded. Tables on electron density, density, refractive indexes, molar refractivity, surface data and dissociation constants of isoxazole and its derivatives have been compiled (62HC(17)l,p. 177). Short reviews on all aspects of the physical properties as applied to isoxazoles have appeared in the series Physical Methods in Heterocyclic Chemistry (1963-1976, vols. 1-6). 

Trioxolane, 3-ethyl-5-butyI-molar refraction, 6, 865 (55CB1878)... 

Now Pe is numerically equal to the molar refraction R which is an additive property. It has been shown that P is a property which can be calculated by adding the refractions of various electron groups. Six values for such partial molar refractions are given in Table 6.3. 

The additive and constitutive properties of the molar refraction of a substance has been known for nearly a century and the molar refraction is defined by the following equation,... 

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