5. Conclusions

The synthesis of the most important classes of the nonlinear optical organic compounds, fullerenes, perylenes, thiophene, azo-dyes dyes, thienes, polymers, and other compounds, along with the techniques employed for the deposition of these compounds, was presented. For the synthesis of the new compounds with nonlinear optical applications, important reactions, like Stille, Suzuki, Knoevenagel, Huisgen, Vilsmeier-Haack-Arnold, click, were employed.

Among the simpler and more sophisticated techniques, the matrix-assisted pulsed laser evaporation (MAPLE) technique that permits making organic films with different morphologies, on different types of substrates, is the main method used to obtain thin laser films, with three basic advantages: the control of thickness; possibility to deposit multilayers; and fabrication of thin films on nonplanar substrates with good surface coverage. Crystallization growth mechanisms in MAPLEdeposited conjugated polymer films that determine specific structure, therefore the carrier transport properties, were discussed in relation with second harmonic generation (SHG) behavior of the thin films.

Author details

Maria Marinescu

15

Faculty of Chemistry, University of Bucharest, Bucharest, Romania

Synthesis and Nonlinear Optical Studies on Organic Compounds in Laser-Deposited Films

DOI: http://dx.doi.org/10.5772/intechopen.83234

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: maria7marinescu@yahoo.com

provided the original work is properly cited.

Organic compounds are cheap, low toxicity, ease of solution processability; therefore, their applications as NLO materials are growing.

### Conflict of interest

The author has no conflict of interest to declare.

Synthesis and Nonlinear Optical Studies on Organic Compounds in Laser-Deposited Films DOI: http://dx.doi.org/10.5772/intechopen.83234
