A toy model for the nonlinear optical response of molecules with modulated conjugation

In organic molecules, the optical response originates from the motion of the pi-electrons, which are constrained to move along the molecule’s conjugated path. As an electron moves through the conjugated path, it interacts with the rest of the charges such that its motion is very dependent on the shape of the molecule. In this paper we introduce a simple model for that allows us to determine how the shape of the conjugated path affects the nonlinear optical response of the molecule. Our results apply to typical second-order dipolar structures: we have determined how the symmetry of the conjugated path affects the optical response, and we have found potential new strategies for making better molecules.