Résumé:

In the present work we develop an approach which associates viral capsid formation with the unconventional crystallization process and propose to describe the capsid self-assembly using a generalization of the Landau theory of crystallization. It is based on the successive application of methods of a) theory of representations of continuous and discrete groups; b) theory of invariants for the groups not-generated by reflections; c) theory of bifurcations of invariant functionals. To compare the predictions of the theory with the available cryoelectronic microscopy and AFM data we use irreducible density distribution functions which generate the protein positions on a spherical capsid.