DENSITY-OF-STATES NEAR THE MOTT-HUBBARD TRANSITION IN THE LIMIT OF LARGE DIMENSIONS

The zero temperature Mott-Hubbard transition as a function of the Coul omb repulsion U is investigated in the Limit of large dimensions. The behavior of the density of states near the transition at U = U-c is an alyzed in all orders of the skeleton expansion. It is shown that only two transition scenarios are consistent with the skeleton expansion fo r U < U-c: (i) The Mott-Hubbard transition is ''discontinuous'' in the sense that in the density of states finite spectral weight is redistr ibuted at U-c. (ii) The transition occurs via a point at U = U-c where the system is neither a Fermi liquid nor an insulator. [S0031-9007(98 )07525-5].