Über den Einfluss nichtpolarer Lösungsmittel auf Lage und Intensität von Absorptionsbanden in den Elektronenspektren apolarer Molekeln: II. Polyacetylene

The dispersive interaction of nonpolar solutes with nonpolar solvents is investigated in model systems consisting of solutions of dimethyl‐tetraacetylene, di‐ t ‐butyl‐tetraacetylene, dimethyl‐pentaacetylene or di‐ t ‐butyl‐pentaacetylene in binary mixtures of cyclohexane/carbondisulfide or n ‐pentan/carbondisulfide. For this purpose the 1 Σ   g +→ 1 Σ   u +transition in the electronic spectrum of the solutions has been recorded. With increasing concentration of the more strongly interacting solvent component ( i.e . carbondisulfide) bathochromic shifts δν of the transition frequency accompanied by a decrease in oscillator strength f M are observed, which are consistent with calculated values based on a previously proposed exciton model [1].