INTERACTION EFFECT IN THE KONDO ENERGY OF THE PERIODIC ANDERSON-HUBBARD MODEL

We extend the periodic Anderson model by switching on a Hubbard U for the conduction band. The nearly integral valent limit of the Anderson- Hubbard model is studied with the Gutzwiller variational method. The l attice Kondo energy shows U dependence both in the prefactor and the e xponent. Switching on U reduces the Kondo scale, which can be understo od to result from the blocking of hybridization. At half filling, we f ind a Brinkman-Rice-type transition from a Kondo insulator to a Mott i nsulator. Our findings should be relevant for a number of correlated t wo-band models of recent interest.