Zakharov A. Optical and non-linear optical properties of п-conjugated oligomers in local coupled cluster theory

A new п-electron quantum-chemical approach basing on the PPP variant unrelaxed CCSD method and using the ideas of the local theory of electron correlation was developed (in HELIOS package) and tested. The high efficiency of the developed cue-CCSD method describing electronic (charge distribution, indices of reactivity), optical (polarizability, energy of electronic transitions) and nonlinear optical effects (first and second hyperpolarizability) for wide range of п-conjugated hydrocarbons (from quasi- to nano) is demonstrated. The reliable limit values of polarizabilities, first and second hyperpolarizabilities for trans-polyenes, polyynes, condensed and non-condensed polyfulvenes, polycalicenes, linear polyacenes, polybenzocyclobutadienes, poly(p quinodimethanes), polyphenylenevinylenes and polystilbenes were obtained.