Preparation and film formation behavior of the supramolecular complex of the endohedral metallofullerene Dy@C82 with calix[8]arene

The first host-guest supramolecular complex of the endohedral metallofullerene Dy@C-82 and p-tert-butylcalix[8]arene (C8A) (1:1) has been prepared in solution. Langmuir films of the [Dy@C-82-C8A] complex have been studied systematically in comparison with films of the [C-60-C8A] complex, The Langmuir film formation of both complexes was found to be sensitively dependent on the initial concentration of the spreading solution. This concentration dependence is explained in terms of conformational changes at different concentrations. While the formation of the complex [C-60-C8A] from the mixture of C-60/C8A was facile at the air/water interface, this was not the case for [Dy@C-82-C8A] due to the slower complexation rate and the aggregation tendency of the endohedral metallofullerene molecules. Langmuir-Blodgett films of the [Dy@C-82-C8A] and [C-60-C8A] complexes have been characterized by UV-vis absorption spectroscopy.