Computational design of benzothiazole-derived push–pull dyes with high molecular quadratic hyperpolarizabilities

Semi-empirical ZINDO SOS and ab initio quadratic response function (DDRPA) calculations on a series of donor–acceptor substituted π-conjugated chromophores based on styryl benzothiazoles are used to aid in the design of dyes with high non-linear optical properties. Structural modifications studied include nature and position of the donor and/or acceptor group as well as the length of the connecting π-bridge. The most worthwhile target for synthesis are 2-tricyanovinyl-6-p-donor-styryl benzothiazoles and heteroaryl derivatives thereof.