Electronic structure and magnetic properties of scandium

The Van Vleck orbital and Pauli spin paramagnetic contributions to the magnetic susceptibility of single-crystal and polycrystalline scandium are calculated using the augmented-plane-wave method in conjunction with a linear-combination-of-atomic-orbitals interpolation scheme, which uses $s-$, $p-$, and $d-$-type functions in the tight-binding representation. The warped-muffin-tin potential was obtained from overlapping charge densities, which were derived from the atomic configuration $3d^{2}4s$; the exchange interaction was included in full Slater ${\rho }^{\frac{1}{3}}$ approximation. The Fermi energy is found to lie in a sharp peak in the density-of-states curve. The anisotropy in the magnetic susceptibility and the low-temperature variation of the susceptibility of scandium, particularly the hump around 25°K observed by Spedding and Croat, are successfully explained. The large enhancement of the low-temperature specific heat due to spin fluctuations calculated from the molecular-field parameter in random-phase approximation is shown to account for the absence of superconductivity in scandium.