Low-Temperature Dynamics of Amorphous Polymers and Evolution over Time of Spectra of Single Impurity Molecules: II. Model Calculations and Analysis of Results

摘要

The results of a statistical analysis of the spectra of single molecules of tetra-tert-butylterrylene in amorphous polyisobutylene at temperatures of 2, 4.5, and 7 K are presented.Model calculations of such spectra for this system are performed in the context of the stochastic theory of the spectra of single molecules in low-temperature glasses. Analysis of the multiplet structure of the experimental and model spectra made it possible to obtain data about the minimal distance between impurity chromophore molecules and two-level systems and about the distribution parameters of their coupling constant. The interaction of achromophore with quasi-local low-frequency vibrational model calculations performed showed that the specific structure of the spectra of single molecules at low temperatures is determined by the interactions with a small number of nearby two-level systems.