Nonlinear optics (NLO) investigates the interactions of applied electromagnetic fields in various materials to generate new electromagnetic fields, altered in frequency, phase or other physical properties. The principle of molecular design on the nonlinear optical materials has been introduced, and taking the long chain conjugated molecules and fullerenes including its derivatives as the examples, our research results have been reported.

Key words: nonlinear optical material, molecular design, ZINDO-SOS