Molecular coefficients

Likewise, quantum mechanical calculation succeeds in giving a theoretical explanation of some facts that the resonance theory could not explain, for example, why bis(pyridine-2)monomethine cyanine and bis(pyridine-4)monomethine cyanine possess the same lowest energy transition contrary to the 2,2 - and 2,4 -quinoline monomethine dyes, together with a molecular coefficient extinction lower than that of the 4,4 -quinoline dye (11). Calculation shows also that there is no theoretical reason for observing a relationship between and pK in a large series of dyes with different nuclei as it has been postulated, even if limited observations and calculations in short homogeneous series could lead to this conclusion (105). 

The molecular coefficient for hydroxyl absorption, n , as measured by Avramenko and Kondratiev6 permitted determination of the absolute values for small concentrations of free hydroxyl. 

Avramenko6 specified the value of the hydroxyl absorption molecular coefficient in a form convenient for use in the determination of hydroxyl concentrations under flame conditions. 

The following equation6 allows for the absorption molecular coefficient (n,) fl as a function of pressure P and temperature T... 

The amylose-iodine interaction has a dipolar nature, as deduced from a distinct difference between the molecular coefficient of iodine in starch and in nonpolar solvents.123 The additional stabilization may result from the formation of resonating polyiodine chains at high dipolar interactions. The composition of the total energy of stabilization is shown5 in Table VI. 

In general, In fully developed turbulent flows the turbulent viscosity, conductivity and diffusivity vary from point to point in the flow field and are many magnitudes greater than the molecular coefficients. 

Since intensive mixing of liquid flows is observed at developed turbulent regime, so according to [136-139] one can t directly apply ordinary equations of continuum movement (for example, Navie-Stocks equation with molecular coefficient of viscosity) in this case. That is why it is generally accepted to use the so-called average equations of turbulent continuum movement, they are also called as average by Remolds. 

Using electrochemical detection in high-performance liquid chromatography, nitroso and nitro diphenylamine can be selectively detected in the presence of other reducible compounds and high concentrations of diphenylamine. Electrochemical detection presents roughly the same response for similar compounds or compounds with the same electroactive groups, while the spectrophotometric response is dependent on the molecular coefficient of absorption for the compounds at the chosen wavelength. 

Table 2.3. Experimental and calculated values of first-order near free molecular coefficient...

The long-range molecular coefficients C are anyway very interesting by themselves they describe exactly the long-range behaviour of the bimolecular system, embodying all dependence on the electric properties which characterize the charge distributions of the individual molecules and their relative orientation in the dimer [23, 63]. 

The coefficients x are applied for the description of the macroscopic susceptibilities instead of the molecular coefficients a, p, and y. The first-order susceptibility x describes linear processes such as refraction and absorption. Nonlinearities are characterized by the susceptibilities of higher order (x , x - ) The even- and odd-order terms lead to different nonlinear responses, is contributed to the polarization only in noncentrosymmetric media, and x contributing in any media irrespective of the symmetry (Prasad and Wilhams, 1991). 

The ultimate goal in this field is the optimization of the molecular coefficients /3. This is the result of a delicate balance between the strength of the polar end groups and the chain length. It is not easy to outline a simple relation between structural parameters and NLO behavior because the different factors that affect the properties... 

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