Materials Data on Np(Al2Fe)4 by Materials Project

Abstract

NpFe4Al8 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Np is bonded in a 12-coordinate geometry to eight equivalent Fe and twelve Al atoms. All Np–Fe bond lengths are 3.32 Å. There are four shorter (2.97 Å) and eight longer (3.15 Å) Np–Al bond lengths. Fe is bonded in a 12-coordinate geometry to two equivalent Np, two equivalent Fe, and eight Al atoms. Both Fe–Fe bond lengths are 2.51 Å. There are four shorter (2.52 Å) and four longer (2.64 Å) Fe–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Np, four equivalent Fe, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.80 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to one Np, four equivalent Fe, and five Al atoms. The Al–Al bond length is 2.75 Å.