The room-temperature optical reflectivity of metallic CrSb, MnSb, NiSb, and NiAs has been measured between 0.05 and 5.0 eV, and the optical constants have been deduced by a Kramers-Kronig analysis. The nickel compounds have a low-energy region of intraband character while CrSb and MnSb show strong interband transitions to the lowest energy measured. This is interpreted as supporting a band model in which there are $3d$ states at the Fermi level for MnSb and CrSb, but not for nickel compounds. The departures of the intraband optical properties of the nickel compounds from Drude behavior are described by a generalized Drude analysis in terms of a complex energy-dependent lifetime, the real part of which has an approximate ${\omega }^2$ dependence.

• Received 4 October 1976

DOI:https://doi.org/10.1103/PhysRevB.15.2952