Fermi surface, effective masses, and energy bands of HfTe_{5} as derived from the Shubnikov–de Haas effect

The Fermi surface of the intermetallic compound ${\mathrm{HfTe}}_5$ has been determined and found to be semimetallic and very similar to that of ${\mathrm{ZrTe}}_5$, consisting of three very small surfaces. The largest, probably of the hole type, has a volume of 7.45×${10}^{16}$ holes/${\mathrm{cm}}^3$ (about (1/4) the holes in bismuth), and the smaller two are of the electron type. All of the surfaces are of ellipsoidal form with principal axes along the orthorhombic unit-cell axes. Each has a similar anisotropy, with the longest axis in the b direction and the smallest in the a direction. Within experimental error the volume of the largest surface is found equal to the sum of volumes of the smaller two surfaces thus demonstrating compensation. Under the assumption of parabolic dispersion relations, the Fermi energy and effective masses are determined. The effective masses are found to be significantly less than those of ${\mathrm{ZrTe}}_5$.