The exact solution of the multi-component Falicov-Kimball model ininfinite-dimensions is presented and used to discuss a new fixed point ofvalence fluctuating intermetallics with Yb and Eu ions. In these compounds,temperature, external magnetic field, pressure, or chemical pressure induce atransition between a metallic state with the f-ions in a mixed-valent(non-magnetic) configuration and a semi-metallic state with the f-ions in anintegral-valence (paramagnetic) configuration. The zero-field transition occursat the temperature Tv, while the zero-temperature transition sets in at thecritical field Hc. We present the thermodynamic and dynamic properties of themodel for an arbitrary concentration of d- and f-electrons. For large U, wefind a MI transition, triggered by the temperature or field-induced change inthe f-occupancy.
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