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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on PrSe by Materials Project

PrSe is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pr is bonded to six equivalent Se atoms to form a mixture of edge and corner-sharing PrSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Pr–Se bond lengths are 3.02 Å. Se is bonded to six equivalent Pr atoms to form a mixture of edge and corner-sharing SePr6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSe2 by Materials Project

PrSe2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Pr4+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Pr–Se bond distances ranging from 3.02–3.27 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four equivalent Pr4+ and one Se2- atom. The Se–Se bond length is 2.54 Å. In the second Se2- site, Se2- is bonded to five equivalent Pr4+ atoms to form a mixture of distorted edge and corner-sharing SePr5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3Se4 by Materials Project

Pr3Se4 crystallizes in the cubic I-43d space group. The structure is three-dimensional. Pr is bonded to eight equivalent Se atoms to form a mixture of distorted corner, edge, and face-sharing PrSe8 hexagonal bipyramids. There are four shorter (3.04 Å) and four longer (3.20 Å) Pr–Se bond lengths. Se is bonded to six equivalent Pr atoms to form a mixture of distorted corner, edge, and face-sharing SePr6 octahedra. The corner-sharing octahedra tilt angles range from 17–50°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSe2 by Materials Project

PrSe2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Pr4+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Pr–Se bond distances ranging from 3.07–3.17 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to five equivalent Pr4+ atoms to form a mixture of distorted edge and corner-sharing SePr5 trigonal bipyramids. In the second Se2- site, Se2- is bonded in a 8-coordinate geometry to four equivalent Pr4+ and four equivalent Se2- atoms. All Se–Se bond lengths are 2.96 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSe2 by Materials Project

PrSe2 crystallizes in the tetragonal P-4b2 space group. The structure is three-dimensional. Pr4+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Pr–Se bond distances ranging from 3.03–3.25 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to five equivalent Pr4+ atoms to form a mixture of distorted corner and edge-sharing SePr5 trigonal bipyramids. In the second Se2- site, Se2- is bonded in a 8-coordinate geometry to four equivalent Pr4+ and two equivalent Se2- atoms. There are one shorter (2.73 Å) and one longer (3.23 Å) Se–Se bond lengths. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to four equivalent Pr4+ and four equivalent Se2- atoms. In the fourth Se2- site, Se2- is bonded in a 8-coordinate geometry to four equivalent Pr4+ atoms.

36 MATERIALS SCIENCE↗