The electronic and magnetic properties of ${\mathrm{LaCo}}_{13}$ are investigated by performing linearized muffin-tin-orbital band-structure calculations for both paramagnetic and ferromagnetic phases. It is found that, for two types of Co atoms in the paramagnetic phase of ${\mathrm{LaCo}}_{13}$, the local density of states of Co(1) atoms at ${\mathit{E}}_{\mathit{F}}$ is smaller than, whereas that of Co(2) atoms is comparable to that of hcp Co metal. Calculated magnetic moments for Co(1) and Co(2) atoms are 1.34${\mathrm{\mu }}_{\mathit{B}}$ and 1.65${\mathrm{\mu }}_{\mathit{B}}$, respectively. The estimated average magnetic moment of Co atoms in the ferromagnetic phase of ${\mathrm{LaCo}}_{13}$ is 1.60${\mathrm{\mu }}_{\mathit{B}}$, in reasonably good agreement with experimental values of 1.56–1.68${\mathrm{\mu }}_{\mathit{B}}$. The electronic structure of unstable ${\mathrm{LaFe}}_{13}$ is also calculated and compared with that of ${\mathrm{LaCo}}_{13}$ in order to discuss the correlation between the structural stability and the electronic structure.

• Received 3 August 1993

DOI:https://doi.org/10.1103/PhysRevB.49.9697