Single-phase films of the full-Heusler compound ${\mathrm{Fe}}_2\mathrm{TiSi}$ have been prepared by magnetron sputtering. The compound is found to be a semiconductor with a gap of 0.4 eV. The electrical resistivity has a logarithmic temperature dependence up to room temperature due to Kondo scattering of a dilute free electron gas off superparamagnetic impurities. The origin of the electron gas is extrinsic due to residual off-stoichiometry. Density functional theory calculations of the electronic structure are in excellent agreement with electron energy loss, optical, and x-ray absorption experiments. ${\mathrm{Fe}}_2\mathrm{TiSi}$ may find applications as a thermoelectric material.

• Received 30 April 2014
• Revised 5 August 2014

DOI:https://doi.org/10.1103/PhysRevB.90.085127