Magnetic Susceptibility and Electronic Structure of CoSi and CoGe Alloys at High Temperatures

The magnetic susceptibility of CoSi and CoGe alloys is investigated by the Faraday method with the help of the pendulum scale in the temperature range 900 to 1800 °C. It is shown that the Curie‐Weiss law is fulfilled both for solid and liquid alloys with Si (Ge) concentrations up to 30 at%. For these alloys the number of noncoupled spins per Co atom and the paramagnetic Curie temperature are calculated after determination of the temperature‐independent contribution to the magnetic susceptibility. Considering the possible localization of 3d‐electrons, a band model of Co alloys is proposed. Basing on this model and considering the connection of the nearest order in the alloys with the crystalline structure of the solid state, the magnetic properties of both solid and liquid alloys are explained.