  The formation of graphen-nanotube composites addresses a few basic problems.
First, both partners are good donors and acceptors of electrons, which
significantly complicates the intermolecular interaction between them leading
to a two-well shape of the ground state energy term. The second problem
concerns odd-electron character of the components. Similarly to high aromatics
and fullerenes, much larger C-C distances provide a considerable weakening of
odd electrons interaction in nanotubes and graphene that necessitates taking
the configurational interaction of odd electrons into account. Avoiding a
severe complication, the broken spin-symmetry approach makes the problem
feasible. Moreover, unrestricted broken-symmetry Hartree-Fock approach
possesses a unique sensitivity in revealing enhanced chemical activity of the
species caused by their partial radicalization in terms of atomic chemical
susceptibility. The chemical susceptibility profiles along the tube and across
their body as well as over graphene sheets form the ground of computational
synthesis of graphen-nanotube composites in due course of the relevant addition
reactions and make it possible to select two main groups of the composites,
conditionally called hammer and cutting-blade structures. The final product
will depend on whether both components of the composition are freely accessible
or one of them is fixed. Thus, in diluted solutions where the first requirement
is met, one can expect the formation of the multi-addend cutting-blade
composites. Oppositely, when either nanotubes or graphene sheets are fixed on
some substrates, the hammer composites will be formed. A particular "cradle"
composite is suggested for an individual graphene sheet to be fixed by a pair
of nanotubes.
