A long-range model adding a repulsive term from SCF calculations and an attractive term from dispersion evaluated in an oblate spheroidal formalism is proposed for the interaction energy between a transition metal atom and a benzene molecule. An analytical form is derived for the total energy of MC 6H 6 complexes versus the distance R between M and the benzene center of mass. Ground state weakly bound ( D e ∼ 200–600 K) at long range ( R e ∼ 4–4.5 Å) are obtained for the three systems ScC 6H 6, VC 6H 6 and NiC 6H 6, confirming the first evidence of these structures previously pointed out from both electric dipole measurements and CASSCF-MRCI calculations.