Materials Data on K2NpO4 by Materials Project

Abstract

K2NpO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.77–3.07 Å. Np6+ is bonded to six O2- atoms to form corner-sharing NpO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.93 Å) and four longer (2.17 Å) Np–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent K1+ and two equivalent Np6+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to five equivalent K1+ and one Np6+ atom.