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Materials Data on Pr2Se3 by Materials Project

Pr2Se3 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are three inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to eight Se2- atoms to form a mixture of distorted edge, face, and corner-sharing PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.01–3.18 Å. In the second Pr3+ site, Pr3+ is bonded to eight Se2- atoms to form a mixture of distorted edge, face, and corner-sharing PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.02–3.25 Å. In the third Pr3+ site, Pr3+ is bonded to eight Se2- atoms to form a mixture of distorted edge, face, and corner-sharing PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 2.98–3.32 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to six Pr3+ atoms. In the second Se2- site, Se2- is bonded to five Pr3+ atoms to form a mixture of distorted edge, face, and corner-sharing SePr5 square pyramids. In the third Se2- site, Se2- is bonded to five Pr3+ atoms to form a mixture of distorted edge, face, and corner-sharing SePr5 square pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Na(Pr2Se3)4 by Materials Project

Na(Pr2Se3)4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Na is bonded to eight Se atoms to form distorted NaSe8 hexagonal bipyramids that share corners with eight equivalent PrSe8 hexagonal bipyramids, edges with four equivalent PrSe8 hexagonal bipyramids, and faces with eight PrSe8 hexagonal bipyramids. There are four shorter (3.05 Å) and four longer (3.29 Å) Na–Se bond lengths. There are three inequivalent Pr sites. In the first Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with two equivalent NaSe8 hexagonal bipyramids, corners with six PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, a faceface with one NaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.00–3.25 Å. In the second Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with eight PrSe8 hexagonal bipyramids, edges with two equivalent NaSe8 hexagonal bipyramids, edges with two equivalent PrSe8 hexagonal bipyramids, and faces with eight PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.01–3.22 Å. In the third Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with eight PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, faces with two equivalent NaSe8 hexagonal bipyramids, and faces with six PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.03–3.25 Å. There are three inequivalent Se sites. In the first Se site, Se is bonded to one Na and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeNaPr5 octahedra. The corner-sharing octahedra tilt angles range from 14–52°. In the second Se site, Se is bonded to one Na and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeNaPr5 octahedra. The corner-sharing octahedra tilt angles range from 19–50°. In the third Se site, Se is bonded to six Pr atoms to form a mixture of distorted edge, face, and corner-sharing SePr6 octahedra. The corner-sharing octahedra tilt angles range from 16–52°.

36 MATERIALS SCIENCE↗

Materials Data on Ca(Pr2Se3)4 by Materials Project

Ca(Pr2Se3)4 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Ca is bonded to eight Se atoms to form distorted CaSe8 hexagonal bipyramids that share corners with eight PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, and faces with eight PrSe8 hexagonal bipyramids. There are a spread of Ca–Se bond distances ranging from 3.01–3.24 Å. There are eight inequivalent Pr sites. In the first Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share a cornercorner with one CaSe8 hexagonal bipyramid, corners with seven PrSe8 hexagonal bipyramids, an edgeedge with one CaSe8 hexagonal bipyramid, edges with three PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.02–3.23 Å. In the second Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share a cornercorner with one CaSe8 hexagonal bipyramid, corners with seven PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.02–3.22 Å. In the third Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with two equivalent CaSe8 hexagonal bipyramids, corners with six PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.02–3.22 Å. In the fourth Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with two equivalent CaSe8 hexagonal bipyramids, corners with six PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.03–3.22 Å. In the fifth Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share a cornercorner with one CaSe8 hexagonal bipyramid, corners with seven PrSe8 hexagonal bipyramids, an edgeedge with one CaSe8 hexagonal bipyramid, edges with three PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.03–3.23 Å. In the sixth Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share a cornercorner with one CaSe8 hexagonal bipyramid, corners with seven PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, a faceface with one CaSe8 hexagonal bipyramid, and faces with seven PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.01–3.22 Å. In the seventh Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with eight PrSe8 hexagonal bipyramids, edges with two equivalent CaSe8 hexagonal bipyramids, edges with two PrSe8 hexagonal bipyramids, and faces with eight PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.03–3.22 Å. In the eighth Pr site, Pr is bonded to eight Se atoms to form distorted PrSe8 hexagonal bipyramids that share corners with eight PrSe8 hexagonal bipyramids, edges with four PrSe8 hexagonal bipyramids, faces with two equivalent CaSe8 hexagonal bipyramids, and faces with six PrSe8 hexagonal bipyramids. There are a spread of Pr–Se bond distances ranging from 3.03–3.21 Å. There are twelve inequivalent Se sites. In the first Se site, Se is bonded to one Ca and five Pr atoms to form distorted SeCaPr5 octahedra that share corners with fifteen SeCaPr5 octahedra, edges with six SeCaPr5 octahedra, and faces with five SePr6 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the second Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. In the third Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the fourth Se site, Se is bonded to six Pr atoms to form a mixture of distorted edge, face, and corner-sharing SePr6 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the fifth Se site, Se is bonded to six Pr atoms to form a mixture of distorted edge, face, and corner-sharing SePr6 octahedra. The corner-sharing octahedra tilt angles range from 16–51°. In the sixth Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the seventh Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the eighth Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the ninth Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the tenth Se site, Se is bonded to six Pr atoms to form distorted SePr6 octahedra that share corners with fifteen SeCaPr5 octahedra, edges with six SeCaPr5 octahedra, and faces with five SePr6 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the eleventh Se site, Se is bonded to one Ca and five Pr atoms to form a mixture of distorted edge, face, and corner-sharing SeCaPr5 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. In the twelfth Se site, Se is bonded to six Pr atoms to form a mixture of distorted edge, face, and corner-sharing SePr6 octahedra. The corner-sharing octahedra tilt angles range from 16–51°.

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