Organic compounds, nonlinear

See also ATR and Reflectance IR Spectroscopy, Applications Biochemical Applications of Raman Spectroscopy Food Science, Applications of Mass Spectrometry Food Science, Appiications of NMR Spectroscopy Fourier Transformation and Sampiing Theory FT-Raman Spectroscopy, Appiications iR Spectrometers, IR Spectroscopy Sample Preparation Methods IR Spectroscopy, Theory IR Spectral Group Frequencies of Organic Compounds Nonlinear Optical Properties Raman Optical Activity, Spectrometers Raman Spectrometers. 

NLO chromophores. Indeed, a close relation often exists between the linear and nonlinear responses of 7i-conjugated organic compounds which are known to present substantial NLO responses [2-4],... 

Catana, C., Gao, H., Orrenius, C., Stouten, P. F. Linear and nonlinear methods in modeling the aqueous solubility of organic compounds. 

Tichonov EA, Shpak MT (1979) Nonlinear optical phenomena in organic compounds. Naukova Dumka, Kijiv (in Rus)... 

Table I lists a variety of organic nonlinear materials which have appeared in the literature their relative powder efficiencies, absorption cutoffs and /3 values (if available) are also provided. These materials are "typical" only in that they represent results from the few classes of organic compounds investigated to date, yet they are instructive in that one learns which molecular properties may be important. A few caveats are in order to avoid misinterpretation of the data in Table I. Except for compound 10 (19) all the powder efficiency and cutoff data are from our own measurements. Powder measurements were performed on ungraded samples using the Nd YAG output at 1.06/t as fundamental since powder efficiency is a function of particle size distribution and a variety of other factors (3) these values are only semiquantitative. The cutoff values are the wavelengths for which 10-4M solutions in ethanol (unless otherwise indicated) have no absorbance. The cutoff values will be similar to those found in crystal state except where intermolecular charge transfer is important in the crystal or the molecule is solvatochromic, this latter effect being quite common for cyanine dyes such as...

The SHG active compounds found in Tables II-VIII are just a small fraction of the hundreds of substances we have screened by the powder technique. Of the active compounds only another small fraction will provide crystals of size and quality as is required for optical application. A program in crystal growth as thorough as the effort which has gone into synthesis must be instituted in order to take full advantage of these materials. Overall, it will suffice to say that the promising nonlinear properties observed from such a small fraction of all the possible organic compounds bodes very well for future endeavor. 

Table III. Nonlinear coefficients of some organic compounds ...

Chiou, C. T., D. E. Kile, D. W. Rutherford, G. Shung, and S. A. Boyd, Sorption of selected organic compounds from water to a peat soil and its humic-acid and humin fractions Potential sources of the sorption nonlinearity , Environ. Sci. Technol., 34,1254-1258 (2000). 

The combination of organic dopants with oriented assemblies of organic compounds with high-order nonlinear polarization or organic substances of large third-order susceptibility, x , with inorganic sol-gel matrices, offers a greatly expanded capability for... 

It is known many organic compounds containing pi electron systems exhibit remarkably large nonlinearities. 

Yan, A., J. Gasteiger, M. Krug, and S. Anzali. 2004. Linear and nonlinear functions on modeling of aqueous solubility of organic compounds by two structure representation metdoCtomput. Aided Mol. Des 18 75-87. 

In terms of improving our ability to predict soil C turnover, we identify five priorities for research (1) The interactive effects of temperature and moisture on microbial decomposition rates, because soils will experience novel and transient conditions (2) the mechanisms governing protection of OM through interactions with mineral surfaces and due to spatial structure (3) the mechanisms leading to slower OM turnover times with depth (4) the potential for nonlinear responses of decomposition to C availability—for example, the role of labile C inputs in stimulating decomposition of less labile OM (i.e., priming) and density-dependent microbial behavior and (5) how the chemical characteristics of organic compounds, as inputs from different plant species, charred (black) carbon, or microbial cell walls and by-products, influence mechanisms of stabilization and turnover. 

This technique has been applied to organic compounds where charge transfer is dominated by one transition this is not often the case for organometallics. The applicability of this technique to organometallics thus far has not been tested there are no reports where solvatochromism has been used to examine the second-order nonlinearities of transition-metal organometallics, and only one report of its application to two organoboron compounds.30... 

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