Nitroaniline nonlinear

Linear and nonlinear responses of the three isomers of nitroaniline... 

Our calculations predict only minor differences between the ground state dipole moments for molecules containing nitro electron acceptors versus those possessing methylsulfonyl. In contrast, the hyperpolarizabilities behave much differently, in that calculated J3Z for the aminonitrostilbenes is about twice that of the aminosulfonylstilbenes and the nitroanilines are more than 5 times more nonlinear than the sulfonylanilines. The hyperpolarizabilities appear to be very sensitive to the details of the electron donors-acceptor interaction and hence accentuate the differences in the a values for nitro and methylsulfonyl. 

The comparison of the two isomeric nitroanilines is that of two similar molecules, one (para) crystallizes in a centrosymmetric, the other (meta) in a non-centro-symmetric manner. (6) Thus, only the meta exhibits nonlinear optical properties. Dimers of these (and several other) nitroanilines were calculated using AMI, and found to be in good agreement with the experimentally determined structures. (7) Here we focus on how these dimers can interact with additional molecules. 

Etter, M. C., Huang, K. S., Frankenbach, G. M. and Adsmond, D. (1991). Control of symmetry and asymmetry in hydrogen-bonded nitroaniline materials. In Materials for nonlinear optics, chemical perspectives (ed. S. R. Marder, J. E. Sohn and G. D. Stuckty), ACS Symposium Series, 455,446-55. [207]... 

As an example we mention the dependence of the free energy of transfer of man-ganese(II) ions from water to water-acetonitrile mixtures on the parameter [85]. It is a complicated nonlinear dependence, which suggests that the interaction of /7-nitroaniline (used in determination of nd manganese(II) with aqueous solutions of acetonitrile is totally different. One may expect that complicated dependences of AG,r or E° EI/2) potentials on parameters of the Lewis basicity or acidity of mixed solvents will be observed for other ions also. Such relationships of the solvation abilities of water-organic solvent mixtures in respect to different cations are determined by several factors ... 

While gas phase work on the h5q5erpolarizability of small molecules has been relatively free of problems concerned with the definitions of measured quantities and their formal relationship to computed quantities, the same cannot be said about solution studies of rather larger organic species. It is the latter that possess the very large nonlinear response functions that are of greatest interest. The prototype system for such studies has been 4-nitroaniline (pNA) and this review is mainly concerned with the relation between the measurements, in vacuo and in solution, of the hyperpolarizabilities of pNA and the closely related molecule, MNA (2-methyl, 4-nitroaniline) to ab initio and DFT calculations of these quantities. 

The increasing interest in obtaining efficient organic optically nonlinear materials resulted in a combinational chemistry approach to their synthesis. The structures of several nitroaniline derivatives (including five Schiff bases), the compounds which belong to a chemical class having potential application as nonlinear optical materials, have been reported4,5. 

A detailed X-ray diffraction experiment and quantum-chemical calculations of N,N-dhnethyl-4-nitroaniline derivatives, also model compounds for optically nonlinear organic materials, revealed that the introduction of a substituent into the ortho- or meta-position with respect to the dimethylamino group resulted in decreasing the contribution of the... 

Electronic and Nonlinear Optical Properties of 2-Methyl-4-Nitroaniline Clusters (M. Guillaume, B. Champagne, F. Castet L. Ducasse)... 

For these classes of conjugated molecular and polymer structures, the principal property is that their nonreson-ant, nonlinear optical responses are dominated by ultrafast, virtual excitations of the ir-electron states. This was directly demonstrated by MNA (2-methyl-4-nitroaniline) single crystal measurements of macroscopic second order susceptibilities at do (j 3) and optical frequencies (13-1 ) and combined second harmonic measurements and theo-... 

---