Optimization of the First and Second Hyperpolarizabilities of Organic Dyes (abstract)

We have been attempting to correlate hyperpolarizabilities with bond-length alteration (BLA), which is defined as the difference in the average length between adjacent carbon-carbon bonds in a polymethine [(CH)(sub n)] Polyenes have alternating double and single bonds (bond length equal to 1.34 Sand 1.45 U respectively), and thus show a high degree of bond-length alteration (BLA = -0.11 u.