SINGLE BAND HUBBARD-MODEL WITH INFINITE REPULSION ON 2X2X2 LATTICE

All the energy eigenvalues of the Hubbard model with infinite repulsion on 2×2×2 cubic lattice for different electron numbers N e are calculated numerically. For Ne=4, 7 the ground state is completely ferromagnetic; namely, total spin S is Ne/2. For Ne=5, the total spin of the ground state is 3/2. For Ne=2, 6, it is zero. For Ne=1, 3, it is 1/2. Thermodynamic quantities such as entropy, susceptibility and specific heat are calculated with the method of canonical ensemble. There are two peaks in the specific heat curve for Ne=4, 5, 6, 7, but only one peak for Ne=1, 2, 3. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.