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PmCl3 crystallizes in the hexagonal P6_3/mmc space group. The structure is one-dimensional and consists of two PmCl3 ribbons oriented in the (0, 0, 1) direction. Pm3+ is bonded to six equivalent Cl1- atoms to form distorted face-sharing PmCl6 pentagonal pyramids. All Pm–Cl bond lengths are 2.75 Å. Cl1- is bonded in an L-shaped geometry to two equivalent Pm3+ atoms.
PmI3 crystallizes in the hexagonal P6_3/mmc space group. The structure is one-dimensional and consists of two PmI3 ribbons oriented in the (0, 0, 1) direction. Pm3+ is bonded to six equivalent I1- atoms to form distorted face-sharing PmI6 pentagonal pyramids. All Pm–I bond lengths are 3.13 Å. I1- is bonded in an L-shaped geometry to two equivalent Pm3+ atoms.
Pm2O3 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Pm3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pm–O bond distances ranging from 2.30–2.67 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Pm3+ atoms to form OPm4 tetrahedra that share corners with six equivalent OPm6 octahedra, corners with six equivalent OPm4 tetrahedra, edges with three equivalent OPm6 octahedra, and edges with three equivalent OPm4 tetrahedra. The corner-sharing octahedra tilt angles range from 18–56°. In the second O2- site, O2- is bonded to six equivalent Pm3+ atoms to form OPm6 octahedra that share corners with twelve equivalent OPm4 tetrahedra, edges with six equivalent OPm6 octahedra, and edges with six equivalent OPm4 tetrahedra.
PmN is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pm3+ is bonded to six equivalent N3- atoms to form a mixture of edge and corner-sharing PmN6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Pm–N bond lengths are 2.56 Å. N3- is bonded to six equivalent Pm3+ atoms to form a mixture of edge and corner-sharing NPm6 octahedra. The corner-sharing octahedral tilt angles are 0°.
PmSe2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Pm3+ is bonded in a 9-coordinate geometry to nine Se+1.50- atoms. There are a spread of Pm–Se bond distances ranging from 3.04–3.13 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded in a 8-coordinate geometry to four equivalent Pm3+ and four equivalent Se+1.50- atoms. All Se–Se bond lengths are 2.93 Å. In the second Se+1.50- site, Se+1.50- is bonded to five equivalent Pm3+ atoms to form a mixture of distorted edge and corner-sharing SePm5 trigonal bipyramids.
PmS2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Pm3+ is bonded in a 9-coordinate geometry to nine S+1.50- atoms. There are a spread of Pm–S bond distances ranging from 2.89–2.99 Å. There are two inequivalent S+1.50- sites. In the first S+1.50- site, S+1.50- is bonded in a 8-coordinate geometry to four equivalent Pm3+ and four equivalent S+1.50- atoms. All S–S bond lengths are 2.79 Å. In the second S+1.50- site, S+1.50- is bonded to five equivalent Pm3+ atoms to form a mixture of distorted edge and corner-sharing SPm5 trigonal bipyramids.
PmAs3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Pm3+ is bonded to twelve As1- atoms to form a mixture of corner, edge, and face-sharing PmAs12 cuboctahedra. There are four shorter (2.94 Å) and eight longer (3.26 Å) Pm–As bond lengths. There are two inequivalent As1- sites. In the first As1- site, As1- is bonded in a 8-coordinate geometry to four equivalent Pm3+ and four equivalent As1- atoms. All As–As bond lengths are 2.94 Å. In the second As1- site, As1- is bonded in a square co-planar geometry to four equivalent Pm3+ atoms.
MgPm2S4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Mg2+ is bonded in a 4-coordinate geometry to eight equivalent S2- atoms. There are four shorter (2.63 Å) and four longer (3.21 Å) Mg–S bond lengths. Pm3+ is bonded in a 8-coordinate geometry to eight equivalent S2- atoms. There are a spread of Pm–S bond distances ranging from 2.76–3.19 Å. S2- is bonded in a 6-coordinate geometry to two equivalent Mg2+ and four equivalent Pm3+ atoms.
PmS3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Pm3+ is bonded to twelve equivalent S1- atoms to form a mixture of distorted face and corner-sharing PmS12 cuboctahedra. There are six shorter (2.86 Å) and six longer (3.24 Å) Pm–S bond lengths. S1- is bonded in a 2-coordinate geometry to four equivalent Pm3+ atoms.
PaPmO4 is Fluorite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Pa5+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pa–O bond lengths are 2.32 Å. Pm3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pm–O bond lengths are 2.42 Å. O2- is bonded to two equivalent Pa5+ and two equivalent Pm3+ atoms to form a mixture of edge and corner-sharing OPm2Pa2 tetrahedra.
MgPm2Se4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent Se2- atoms to form MgSe4 tetrahedra that share corners with twelve equivalent PmSe6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Mg–Se bond lengths are 2.65 Å. Pm3+ is bonded to six equivalent Se2- atoms to form PmSe6 octahedra that share corners with six equivalent MgSe4 tetrahedra and edges with six equivalent PmSe6 octahedra. All Pm–Se bond lengths are 2.95 Å. Se2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three equivalent Pm3+ atoms.
PaPmO4 is Fluorite-derived structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Pa5+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pa–O bond lengths are 2.31 Å. Pm3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Pm–O bond lengths are 2.43 Å. O2- is bonded to two equivalent Pa5+ and two equivalent Pm3+ atoms to form a mixture of edge and corner-sharing OPm2Pa2 tetrahedra.
PmSe2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Pm3+ is bonded in a 9-coordinate geometry to nine Se+1.50- atoms. There are a spread of Pm–Se bond distances ranging from 2.98–3.22 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded in a 5-coordinate geometry to four equivalent Pm3+ and one Se+1.50- atom. The Se–Se bond length is 2.55 Å. In the second Se+1.50- site, Se+1.50- is bonded to five equivalent Pm3+ atoms to form a mixture of distorted edge and corner-sharing SePm5 trigonal bipyramids.
PmSe3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Pm3+ is bonded to twelve Se1- atoms to form distorted PmSe12 cuboctahedra that share corners with four equivalent PmSe12 cuboctahedra, edges with eight equivalent PmSe12 cuboctahedra, edges with sixteen equivalent SePm4Se8 cuboctahedra, faces with four equivalent PmSe12 cuboctahedra, and faces with eight equivalent SePm4Se8 cuboctahedra. There are four shorter (2.94 Å) and eight longer (3.40 Å) Pm–Se bond lengths. There are two inequivalent Se1- sites. In the first Se1- site, Se1- is bonded to four equivalent Pm3+ and eight Se1- atoms to form distorted SePm4Se8 cuboctahedra that share corners with twelve equivalent SePm4Se8 cuboctahedra, edges with eight equivalent PmSe12 cuboctahedra, edges with eight equivalent SePm4Se8 cuboctahedra, faces with four equivalent PmSe12 cuboctahedra, and faces with ten equivalent SePm4Se8 cuboctahedra. There are four shorter (2.94 Å) and four longer (3.40 Å) Se–Se bond lengths. In the second Se1- site, Se1- is bonded in a square co-planar geometry to four equivalent Pm3+ and eight equivalent Se1- atoms.
MgPmS3 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Mg2+ is bonded to six S+1.67- atoms to form distorted MgS6 octahedra that share corners with four equivalent PmS6 pentagonal pyramids, edges with three equivalent MgS6 octahedra, and edges with four equivalent PmS6 pentagonal pyramids. There are a spread of Mg–S bond distances ranging from 2.55–2.88 Å. Pm3+ is bonded to six S+1.67- atoms to form distorted PmS6 pentagonal pyramids that share corners with four equivalent MgS6 octahedra, edges with four equivalent MgS6 octahedra, an edgeedge with one PmS6 pentagonal pyramid, and a faceface with one PmS6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 38–48°. There are a spread of Pm–S bond distances ranging from 2.74–2.99 Å. There are two inequivalent S+1.67- sites. In the first S+1.67- site, S+1.67- is bonded in a 4-coordinate geometry to two equivalent Mg2+ and two equivalent Pm3+ atoms. In the second S+1.67- site, S+1.67- is bonded to two equivalent Mg2+ and two equivalent Pm3+ atoms to form edge-sharing SPm2Mg2 trigonal pyramids.
Pm2(WO4)3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Pm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pm–O bond distances ranging from 2.39–2.51 Å. There are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of W–O bond distances ranging from 1.78–2.16 Å. In the second W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.80 Å) and two longer (1.85 Å) W–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Pm3+ and two equivalent W6+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Pm3+ and one W6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Pm3+ and one W6+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Pm3+ and one W6+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Pm3+ and one W6+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Pm3+ and one W6+ atom.
MgPm2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent S2- atoms to form MgS4 tetrahedra that share corners with twelve equivalent PmS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Mg–S bond lengths are 2.53 Å. Pm3+ is bonded to six equivalent S2- atoms to form PmS6 octahedra that share corners with six equivalent MgS4 tetrahedra and edges with six equivalent PmS6 octahedra. All Pm–S bond lengths are 2.83 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three equivalent Pm3+ atoms.
PmP3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Pm3+ is bonded to twelve P1- atoms to form a mixture of corner, edge, and face-sharing PmP12 cuboctahedra. There are four shorter (2.81 Å) and eight longer (3.12 Å) Pm–P bond lengths. There are two inequivalent P1- sites. In the first P1- site, P1- is bonded in a 8-coordinate geometry to four equivalent Pm3+ and four equivalent P1- atoms. All P–P bond lengths are 2.81 Å. In the second P1- site, P1- is bonded in a square co-planar geometry to four equivalent Pm3+ atoms.