Coupling strength distributions for dynamic interactions experienced by probe molecules in a polymer host

In this work, discrepancies between measured single-molecule linewidth dist ributions and distributions simulated with the standard tunneling model in the sudden-jump approximation are studied for terrylene and di-tert-butylte nylene dopant molecules in poly(vinylbutyral). The experimental data has be en carefully checked for systematic errors. It is shown that the results ar e in disagreement with the standard model, but that the incorporation of a distribution of molecule-polymer coupling strengths would remove this disag reement. Additionally, the experimental observation of a surprising correla tion between the single-molecule line areas and the matrix-molecule interac tion strength is presented, and a hypothesis is put forward for its physica l origin.