Geometry and electronic structure of the dimers and trimers in CB5 molecule were studied by quantum-mechanical DFT method in the software package Gaussian 09. The influence of different types hybrid potentials on the results of the calculations was investigated. It is shown that the convergence process in the optimization of the geometry is more reliably implemented using B3LYP method. Binding energy in the associates obtained by different DFT methods are approximately the same. Bibliogr. 12. Il. 2. Tables 3.