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DOE OSTI2020

Materials Data on La2ThTa(ClO2)3 by Materials Project

ThLa2Ta(O2Cl)3 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent Th4+ sites. In the first Th4+ site, Th4+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of Th–O bond distances ranging from 2.33–2.62 Å. There are a spread of Th–Cl bond distances ranging from 3.08–3.12 Å. In the second Th4+ site, Th4+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of Th–O bond distances ranging from 2.30–2.73 Å. There are one shorter (3.05 Å) and three longer (3.12 Å) Th–Cl bond lengths. There are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of La–O bond distances ranging from 2.44–2.77 Å. There are three shorter (3.08 Å) and one longer (3.09 Å) La–Cl bond lengths. In the second La3+ site, La3+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of La–O bond distances ranging from 2.44–2.60 Å. There are a spread of La–Cl bond distances ranging from 3.02–3.10 Å. In the third La3+ site, La3+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of La–O bond distances ranging from 2.44–2.69 Å. There are a spread of La–Cl bond distances ranging from 2.98–3.10 Å. In the fourth La3+ site, La3+ is bonded in a 10-coordinate geometry to six O2- and four Cl1- atoms. There are a spread of La–O bond distances ranging from 2.41–2.73 Å. There are two shorter (3.05 Å) and two longer (3.10 Å) La–Cl bond lengths. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded in a distorted pentagonal pyramidal geometry to six O2- atoms. There are two shorter (2.00 Å) and four longer (2.02 Å) Ta–O bond lengths. In the second Ta5+ site, Ta5+ is bonded in a distorted pentagonal pyramidal geometry to six O2- atoms. There are two shorter (1.99 Å) and four longer (2.02 Å) Ta–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Th4+, two La3+, one Ta5+, and one Cl1- atom. The O–Cl bond length is 3.08 Å. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Th4+, two La3+, and one Ta5+ atom. In the third O2- site, O2- is bonded to three La3+ and one Ta5+ atom to form distorted OLa3Ta tetrahedra that share corners with two equivalent OLa2ThTaCl tetrahedra and edges with three OLa3Ta tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Th4+, one La3+, and one Ta5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Th4+, two La3+, and one Ta5+ atom. In the sixth O2- site, O2- is bonded to one Th4+, two La3+, one Ta5+, and one Cl1- atom to form distorted OLa2ThTaCl tetrahedra that share corners with two equivalent OLa3Ta tetrahedra, edges with two OLa3Ta tetrahedra, and a faceface with one OLa2ThTaCl tetrahedra. The O–Cl bond length is 3.05 Å. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 4-coordinate geometry to one Th4+ and three La3+ atoms. In the second Cl1- site, Cl1- is bonded in a 4-coordinate geometry to two Th4+ and two equivalent La3+ atoms. In the third Cl1- site, Cl1- is bonded in a 4-coordinate geometry to one Th4+ and three La3+ atoms. In the fourth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to two equivalent Th4+ and two La3+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to four La3+ atoms. In the sixth Cl1- site, Cl1- is bonded in a 4-coordinate geometry to two equivalent Th4+, two La3+, and four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Au by Materials Project

La2Au is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded to four equivalent Au atoms to form a mixture of distorted corner and edge-sharing LaAu4 tetrahedra. There are a spread of La–Au bond distances ranging from 3.08–3.22 Å. In the second La site, La is bonded in a 3-coordinate geometry to five equivalent Au atoms. There are a spread of La–Au bond distances ranging from 3.25–3.79 Å. Au is bonded in a 9-coordinate geometry to nine La atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2(TlPb)3 by Materials Project

La2(TlPb)3 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. La is bonded to six Tl and six Pb atoms to form LaTl6Pb6 cuboctahedra that share corners with eight TlLa4Pb4 cuboctahedra, corners with twelve equivalent LaTl6Pb6 cuboctahedra, edges with eight TlLa4Pb4 cuboctahedra, edges with twelve PbLa4Tl6Pb2 cuboctahedra, faces with two equivalent TlLa4Pb8 cuboctahedra, faces with six equivalent LaTl6Pb6 cuboctahedra, and faces with six PbLa4Tl6Pb2 cuboctahedra. There are two shorter (3.46 Å) and four longer (3.51 Å) La–Tl bond lengths. There are two shorter (3.45 Å) and four longer (3.51 Å) La–Pb bond lengths. There are three inequivalent Tl sites. In the first Tl site, Tl is bonded to four equivalent La and four equivalent Pb atoms to form distorted TlLa4Pb4 cuboctahedra that share corners with eight equivalent LaTl6Pb6 cuboctahedra, corners with sixteen PbLa4Tl6Pb2 cuboctahedra, edges with four equivalent LaTl6Pb6 cuboctahedra, edges with four equivalent PbLa4Tl6Pb2 cuboctahedra, edges with twelve TlLa4Pb4 cuboctahedra, faces with two equivalent PbLa4Tl4Pb4 cuboctahedra, and faces with four equivalent TlLa4Pb4 cuboctahedra. All Tl–Pb bond lengths are 3.49 Å. In the second Tl site, Tl is bonded to four equivalent La and eight Pb atoms to form TlLa4Pb8 cuboctahedra that share corners with twelve TlLa4Pb8 cuboctahedra, edges with eight equivalent LaTl6Pb6 cuboctahedra, edges with eight equivalent TlLa4Pb4 cuboctahedra, edges with eight equivalent PbLa4Tl6Pb2 cuboctahedra, faces with four equivalent LaTl6Pb6 cuboctahedra, faces with six TlLa4Pb8 cuboctahedra, and faces with eight PbLa4Tl6Pb2 cuboctahedra. There are four shorter (3.47 Å) and four longer (3.51 Å) Tl–Pb bond lengths. In the third Tl site, Tl is bonded to four equivalent La and four equivalent Pb atoms to form distorted TlLa4Pb4 cuboctahedra that share corners with eight equivalent LaTl6Pb6 cuboctahedra, corners with eight equivalent TlLa4Pb8 cuboctahedra, corners with eight equivalent PbLa4Tl6Pb2 cuboctahedra, edges with four equivalent LaTl6Pb6 cuboctahedra, edges with four equivalent TlLa4Pb4 cuboctahedra, edges with twelve PbLa4Tl6Pb2 cuboctahedra, and faces with six TlLa4Pb4 cuboctahedra. All Tl–Pb bond lengths are 3.49 Å. There are two inequivalent Pb sites. In the first Pb site, Pb is bonded to four equivalent La, six Tl, and two equivalent Pb atoms to form distorted PbLa4Tl6Pb2 cuboctahedra that share corners with eight TlLa4Pb4 cuboctahedra, corners with twelve equivalent PbLa4Tl6Pb2 cuboctahedra, edges with four equivalent PbLa4Tl4Pb4 cuboctahedra, edges with eight equivalent LaTl6Pb6 cuboctahedra, edges with eight TlLa4Pb4 cuboctahedra, faces with two equivalent TlLa4Pb8 cuboctahedra, faces with four equivalent LaTl6Pb6 cuboctahedra, and faces with eight PbLa4Tl6Pb2 cuboctahedra. Both Pb–Pb bond lengths are 3.47 Å. In the second Pb site, Pb is bonded to four equivalent La, four equivalent Tl, and four equivalent Pb atoms to form distorted PbLa4Tl4Pb4 cuboctahedra that share corners with four equivalent PbLa4Tl4Pb4 cuboctahedra, corners with eight equivalent TlLa4Pb4 cuboctahedra, edges with eight equivalent LaTl6Pb6 cuboctahedra, edges with eight equivalent TlLa4Pb4 cuboctahedra, edges with eight equivalent PbLa4Tl6Pb2 cuboctahedra, faces with four equivalent LaTl6Pb6 cuboctahedra, faces with six TlLa4Pb4 cuboctahedra, and faces with eight PbLa4Tl6Pb2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La8Te3SeO8 by Materials Project

La8Te3SeO8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 4-coordinate geometry to four equivalent Se2- and four equivalent O2- atoms. All La–Se bond lengths are 3.55 Å. All La–O bond lengths are 2.39 Å. In the second La3+ site, La3+ is bonded in a 4-coordinate geometry to four equivalent Te2- and four equivalent O2- atoms. All La–Te bond lengths are 3.57 Å. All La–O bond lengths are 2.38 Å. In the third La3+ site, La3+ is bonded in a 4-coordinate geometry to four equivalent Te2- and four equivalent O2- atoms. All La–Te bond lengths are 3.57 Å. All La–O bond lengths are 2.38 Å. In the fourth La3+ site, La3+ is bonded in a 4-coordinate geometry to four equivalent Te2- and four equivalent O2- atoms. All La–Te bond lengths are 3.58 Å. All La–O bond lengths are 2.38 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted body-centered cubic geometry to eight La3+ atoms. In the second Te2- site, Te2- is bonded in a distorted body-centered cubic geometry to eight equivalent La3+ atoms. Se2- is bonded in a body-centered cubic geometry to eight equivalent La3+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the second O2- site, O2- is bonded to four La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaMg2 by Materials Project

Mg2La crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six Mg and six equivalent La atoms to form distorted MgLa6Mg6 cuboctahedra that share corners with six equivalent LaLa2Mg10 cuboctahedra, corners with twelve MgLa6Mg6 cuboctahedra, edges with seven equivalent LaLa2Mg10 cuboctahedra, edges with eleven equivalent MgLa4Mg8 cuboctahedra, faces with six equivalent LaLa2Mg10 cuboctahedra, and faces with fourteen MgLa6Mg6 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.38–3.48 Å. All Mg–La bond lengths are 3.43 Å. In the second Mg site, Mg is bonded to eight Mg and four equivalent La atoms to form distorted MgLa4Mg8 cuboctahedra that share corners with six equivalent LaLa2Mg10 cuboctahedra, corners with twelve MgLa6Mg6 cuboctahedra, edges with three equivalent LaLa2Mg10 cuboctahedra, edges with fifteen MgLa6Mg6 cuboctahedra, faces with eight equivalent LaLa2Mg10 cuboctahedra, and faces with twelve MgLa6Mg6 cuboctahedra. There are two shorter (3.39 Å) and four longer (3.47 Å) Mg–Mg bond lengths. There are two shorter (3.45 Å) and two longer (3.50 Å) Mg–La bond lengths. La is bonded to ten Mg and two equivalent La atoms to form LaLa2Mg10 cuboctahedra that share corners with six equivalent LaLa2Mg10 cuboctahedra, corners with twelve MgLa6Mg6 cuboctahedra, edges with eight equivalent LaLa2Mg10 cuboctahedra, edges with ten MgLa6Mg6 cuboctahedra, faces with six equivalent LaLa2Mg10 cuboctahedra, and faces with fourteen MgLa6Mg6 cuboctahedra. Both La–La bond lengths are 3.39 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsLaCl4O3 by Materials Project

CsLaO3Cl4 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Cs is bonded in a 7-coordinate geometry to one O and six Cl atoms. The Cs–O bond length is 3.31 Å. There are a spread of Cs–Cl bond distances ranging from 3.60–3.70 Å. La is bonded in a 3-coordinate geometry to three O and six Cl atoms. There are a spread of La–O bond distances ranging from 2.39–2.53 Å. There are a spread of La–Cl bond distances ranging from 2.92–2.96 Å. There are three inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Cs and one La atom. In the second O site, O is bonded in a single-bond geometry to one La and two equivalent Cl atoms. Both O–Cl bond lengths are 2.48 Å. In the third O site, O is bonded in a single-bond geometry to one La and two equivalent Cl atoms. Both O–Cl bond lengths are 2.47 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a 3-coordinate geometry to one Cs and two equivalent La atoms. In the second Cl site, Cl is bonded in a 3-coordinate geometry to two equivalent Cs, one La, and two O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Si(IO2)2 by Materials Project

La2Si(O2I)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two La2Si(O2I)2 sheets oriented in the (0, 0, 1) direction. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 8-coordinate geometry to five O2- and three I1- atoms. There are a spread of La–O bond distances ranging from 2.39–2.66 Å. There are a spread of La–I bond distances ranging from 3.33–3.39 Å. In the second La3+ site, La3+ is bonded in a 8-coordinate geometry to five O2- and three I1- atoms. There are a spread of La–O bond distances ranging from 2.41–2.67 Å. There are two shorter (3.33 Å) and one longer (3.38 Å) La–I bond lengths. In the third La3+ site, La3+ is bonded in a 9-coordinate geometry to seven O2- and two I1- atoms. There are a spread of La–O bond distances ranging from 2.40–2.96 Å. There are one shorter (3.31 Å) and one longer (3.49 Å) La–I bond lengths. In the fourth La3+ site, La3+ is bonded in a 9-coordinate geometry to seven O2- and two I1- atoms. There are a spread of La–O bond distances ranging from 2.41–2.98 Å. There are one shorter (3.29 Å) and one longer (3.50 Å) La–I bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the second Si4+ site, Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Si4+ atom. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded in a 2-coordinate geometry to two La3+ atoms. In the second I1- site, I1- is bonded in a 2-coordinate geometry to two La3+ atoms. In the third I1- site, I1- is bonded in a 3-coordinate geometry to three La3+ atoms. In the fourth I1- site, I1- is bonded in a 3-coordinate geometry to three La3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAsIr by Materials Project

LaIrAs is hexagonal omega structure-derived structured and crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. La is bonded to six Ir and six equivalent As atoms to form a mixture of edge and face-sharing LaAs6Ir6 cuboctahedra. There are two shorter (3.22 Å) and four longer (3.28 Å) La–Ir bond lengths. There are four shorter (3.21 Å) and two longer (3.35 Å) La–As bond lengths. There are three inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent La and three equivalent As atoms. There are two shorter (2.47 Å) and one longer (2.48 Å) Ir–As bond lengths. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent La and three equivalent As atoms. There are two shorter (2.47 Å) and one longer (2.48 Å) Ir–As bond lengths. In the third Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent La and three equivalent As atoms. There are two shorter (3.22 Å) and four longer (3.28 Å) Ir–La bond lengths. There are two shorter (2.47 Å) and one longer (2.48 Å) Ir–As bond lengths. As is bonded in a 9-coordinate geometry to six equivalent La and three Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiLa5Si4N10O by Materials Project

LiLa5Si4N10O crystallizes in the triclinic P1 space group. The structure is three-dimensional. Li1+ is bonded to five N3- and one O2- atom to form distorted LiN5O octahedra that share corners with six SiN4 tetrahedra and faces with two equivalent LaN7O hexagonal bipyramids. There are a spread of Li–N bond distances ranging from 2.02–2.83 Å. The Li–O bond length is 2.68 Å. There are five inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of La–N bond distances ranging from 2.42–2.97 Å. In the second La3+ site, La3+ is bonded in a 6-coordinate geometry to five N3- and one O2- atom. There are a spread of La–N bond distances ranging from 2.49–2.98 Å. The La–O bond length is 2.45 Å. In the third La3+ site, La3+ is bonded in a 8-coordinate geometry to eight N3- atoms. There are a spread of La–N bond distances ranging from 2.50–3.13 Å. In the fourth La3+ site, La3+ is bonded in a 8-coordinate geometry to seven N3- and one O2- atom. There are a spread of La–N bond distances ranging from 2.49–3.06 Å. The La–O bond length is 2.70 Å. In the fifth La3+ site, La3+ is bonded to seven N3- and one O2- atom to form distorted LaN7O hexagonal bipyramids that share corners with two SiN4 tetrahedra, edges with four SiN4 tetrahedra, and faces with two equivalent LiN5O octahedra. There are a spread of La–N bond distances ranging from 2.42–2.89 Å. The La–O bond length is 2.88 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one LiN5O octahedra, corners with three SiN3O tetrahedra, and an edgeedge with one LaN7O hexagonal bipyramid. The corner-sharing octahedral tilt angles are 49°. There are a spread of Si–N bond distances ranging from 1.71–1.75 Å. In the second Si4+ site, Si4+ is bonded to three N3- and one O2- atom to form SiN3O tetrahedra that share a cornercorner with one LiN5O octahedra, corners with three SiN4 tetrahedra, and an edgeedge with one LaN7O hexagonal bipyramid. The corner-sharing octahedral tilt angles are 52°. There is one shorter (1.72 Å) and two longer (1.73 Å) Si–N bond length. The Si–O bond length is 1.67 Å. In the third Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one LaN7O hexagonal bipyramid, corners with two equivalent LiN5O octahedra, corners with two SiN4 tetrahedra, and an edgeedge with one LaN7O hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 12–57°. There are a spread of Si–N bond distances ranging from 1.73–1.77 Å. In the fourth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one LaN7O hexagonal bipyramid, corners with two equivalent LiN5O octahedra, corners with two SiN4 tetrahedra, and an edgeedge with one LaN7O hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 13–57°. There are a spread of Si–N bond distances ranging from 1.73–1.78 Å. There are ten inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted linear geometry to four La3+ and two Si4+ atoms. In the second N3- site, N3- is bonded in a 2-coordinate geometry to four La3+ and two Si4+ atoms. In the third N3- site, N3- is bonded in a 2-coordinate geometry to four La3+ and two Si4+ atoms. In the fourth N3- site, N3- is bonded in a 4-coordinate geometry to two La3+ and two Si4+ atoms. In the fifth N3- site, N3- is bonded in a 4-coordinate geometry to two La3+ and two Si4+ atoms. In the sixth N3- site, N3- is bonded in a 1-coordinate geometry to one Li1+, three La3+, and one Si4+ atom. In the seventh N3- site, N3- is bonded in a 1-coordinate geometry to one Li1+, three La3+, and one Si4+ atom. In the eighth N3- site, N3- is bonded in a 6-coordinate geometry to one Li1+, four La3+, and one Si4+ atom. In the ninth N3- site, N3- is bonded in a 6-coordinate geometry to one Li1+, four La3+, and one Si4+ atom. In the tenth N3- site, N3- is bonded in a 5-coordinate geometry to one Li1+, three La3+, and one Si4+ atom. O2- is bonded in a 1-coordinate geometry to one Li1+, three La3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Fe(SeO)2 by Materials Project

La2Fe(SeO)2 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 4-coordinate geometry to four Se2- and four O2- atoms. There are a spread of La–Se bond distances ranging from 3.22–3.53 Å. There are a spread of La–O bond distances ranging from 2.38–2.48 Å. In the second La3+ site, La3+ is bonded in a 4-coordinate geometry to four Se2- and four O2- atoms. There are a spread of La–Se bond distances ranging from 3.22–3.48 Å. There are a spread of La–O bond distances ranging from 2.39–2.45 Å. In the third La3+ site, La3+ is bonded in a 3-coordinate geometry to five Se2- and three O2- atoms. There are a spread of La–Se bond distances ranging from 3.10–3.46 Å. There are one shorter (2.35 Å) and two longer (2.40 Å) La–O bond lengths. In the fourth La3+ site, La3+ is bonded in a 3-coordinate geometry to five Se2- and three O2- atoms. There are a spread of La–Se bond distances ranging from 3.14–3.33 Å. There are a spread of La–O bond distances ranging from 2.33–2.40 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a distorted linear geometry to four Se2- and two O2- atoms. There are a spread of Fe–Se bond distances ranging from 2.87–2.96 Å. There is one shorter (1.97 Å) and one longer (1.98 Å) Fe–O bond length. In the second Fe2+ site, Fe2+ is bonded to four Se2- atoms to form corner-sharing FeSe4 tetrahedra. There are a spread of Fe–Se bond distances ranging from 2.53–2.62 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to six La3+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to two La3+ and four Fe2+ atoms. In the third Se2- site, Se2- is bonded in a 1-coordinate geometry to four La3+ and three Fe2+ atoms. In the fourth Se2- site, Se2- is bonded in a 1-coordinate geometry to six La3+ and one Fe2+ atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three La3+ and one Fe2+ atom to form OLa3Fe tetrahedra that share corners with four OLa3Fe tetrahedra and edges with two equivalent OLa4 tetrahedra. In the second O2- site, O2- is bonded to three La3+ and one Fe2+ atom to form OLa3Fe tetrahedra that share corners with four OLa3Fe tetrahedra and edges with two equivalent OLa4 tetrahedra. In the third O2- site, O2- is bonded to four La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the fourth O2- site, O2- is bonded to four La3+ atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaN3O13 by Materials Project

LaN3O13 crystallizes in the monoclinic P2_1/m space group. The structure is two-dimensional and consists of two LaN3O13 sheets oriented in the (0, 1, 0) direction. La is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of La–O bond distances ranging from 2.48–3.20 Å. There are two inequivalent N sites. In the first N site, N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.26 Å) and two longer (1.27 Å) N–O bond length. In the second N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.23–1.29 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one La and one N atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one La and one N atom. In the third O site, O is bonded in a distorted single-bond geometry to one La and one N atom. In the fourth O site, O is bonded in a single-bond geometry to one N atom. In the fifth O site, O is bonded in a distorted water-like geometry to one La and one N atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one La and one O atom. The O–O bond length is 1.23 Å. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to three O atoms. Both O–O bond lengths are 1.68 Å. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one La and one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaY9Si8 by Materials Project

LaY9Si8 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. La is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of La–Si bond distances ranging from 3.10–3.62 Å. There are nine inequivalent Y sites. In the first Y site, Y is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Y–Si bond distances ranging from 2.88–3.02 Å. In the second Y site, Y is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Y–Si bond distances ranging from 2.85–3.03 Å. In the third Y site, Y is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Y–Si bond distances ranging from 2.89–3.03 Å. In the fourth Y site, Y is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Y–Si bond distances ranging from 2.89–3.04 Å. In the fifth Y site, Y is bonded to six Si atoms to form a mixture of distorted face and corner-sharing YSi6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. There are a spread of Y–Si bond distances ranging from 2.93–3.31 Å. In the sixth Y site, Y is bonded to six Si atoms to form a mixture of distorted face and corner-sharing YSi6 octahedra. The corner-sharing octahedra tilt angles range from 55–56°. There are a spread of Y–Si bond distances ranging from 2.96–3.26 Å. In the seventh Y site, Y is bonded in a 6-coordinate geometry to seven Si atoms. There are a spread of Y–Si bond distances ranging from 3.05–3.68 Å. In the eighth Y site, Y is bonded to six Si atoms to form a mixture of distorted face and corner-sharing YSi6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Y–Si bond distances ranging from 3.03–3.15 Å. In the ninth Y site, Y is bonded to six Si atoms to form a mixture of distorted face and corner-sharing YSi6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 44°. There are a spread of Y–Si bond distances ranging from 3.09–3.18 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to eight Y and one Si atom. The Si–Si bond length is 2.54 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to two equivalent La, six Y, and one Si atom. The Si–Si bond length is 2.55 Å. In the third Si site, Si is bonded in a 9-coordinate geometry to eight Y and one Si atom. In the fourth Si site, Si is bonded in a 9-coordinate geometry to one La, seven Y, and one Si atom. In the fifth Si site, Si is bonded in a 9-coordinate geometry to one La, seven Y, and one Si atom. The Si–Si bond length is 2.50 Å. In the sixth Si site, Si is bonded in a 9-coordinate geometry to one La, seven Y, and one Si atom. The Si–Si bond length is 2.53 Å. In the seventh Si site, Si is bonded in a 8-coordinate geometry to one La, six Y, and one Si atom. In the eighth Si site, Si is bonded in a 8-coordinate geometry to one La, six Y, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3La4O9 by Materials Project

La4Sr3O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to five O2- atoms to form distorted SrO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, a cornercorner with one LaO4 tetrahedra, a cornercorner with one SrO5 trigonal bipyramid, corners with two equivalent LaO4 trigonal pyramids, and an edgeedge with one LaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 81°. There are a spread of Sr–O bond distances ranging from 2.42–2.67 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.06 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.42–3.16 Å. In the fourth Sr2+ site, Sr2+ is bonded to five O2- atoms to form distorted SrO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, corners with two equivalent LaO4 tetrahedra, a cornercorner with one SrO5 trigonal bipyramid, corners with two LaO5 trigonal bipyramids, a cornercorner with one LaO4 trigonal pyramid, and an edgeedge with one LaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 38°. There are a spread of Sr–O bond distances ranging from 2.43–2.75 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.39–3.13 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.34–2.82 Å. There are eight inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to five O2- atoms to form distorted LaO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, a cornercorner with one LaO4 tetrahedra, a cornercorner with one SrO5 trigonal bipyramid, a cornercorner with one LaO4 trigonal pyramid, an edgeedge with one SrO5 trigonal bipyramid, and an edgeedge with one LaO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 69°. There are a spread of La–O bond distances ranging from 2.31–2.56 Å. In the second La3+ site, La3+ is bonded in a 5-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.29–3.10 Å. In the third La3+ site, La3+ is bonded to five O2- atoms to form distorted LaO5 trigonal bipyramids that share a cornercorner with one LaO4 tetrahedra, a cornercorner with one LaO5 trigonal bipyramid, an edgeedge with one SrO5 trigonal bipyramid, and an edgeedge with one LaO5 trigonal bipyramid. There are a spread of La–O bond distances ranging from 2.24–2.52 Å. In the fourth La3+ site, La3+ is bonded to five O2- atoms to form LaO5 trigonal bipyramids that share a cornercorner with one LaO4 tetrahedra, a cornercorner with one SrO5 trigonal bipyramid, a cornercorner with one LaO5 trigonal bipyramid, and an edgeedge with one LaO6 octahedra. There are a spread of La–O bond distances ranging from 2.29–2.42 Å. In the fifth La3+ site, La3+ is bonded to four O2- atoms to form LaO4 trigonal pyramids that share a cornercorner with one LaO6 octahedra, a cornercorner with one LaO5 trigonal bipyramid, corners with three SrO5 trigonal bipyramids, and an edgeedge with one LaO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of La–O bond distances ranging from 2.23–2.42 Å. In the sixth La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of La–O bond distances ranging from 2.35–3.05 Å. In the seventh La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share a cornercorner with one LaO5 trigonal bipyramid, corners with two SrO5 trigonal bipyramids, a cornercorner with one LaO4 trigonal pyramid, and an edgeedge with one LaO5 trigonal bipyramid. There are a spread of La–O bond distances ranging from 2.31–2.63 Å. In the eighth La3+ site, La3+ is bonded to four O2- atoms to form distorted LaO4 tetrahedra that share corners with three SrO5 trigonal bipyramids, corners with three LaO5 trigonal bipyramids, and an edgeedge with one LaO4 trigonal pyramid. There are a spread of La–O bond distances ranging from 2.19–2.37 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to three Sr2+ and one La3+ atom. In the second O2- site, O2- is bonded in a distorted see-saw-like geometry to two Sr2+ and two La3+ atoms. In the third O2- site, O2- is bonded to two Sr2+ and three La3+ atoms to form OSr2La3 trigonal bipyramids that share corners with two OSrLa3 tetrahedra, corners with three OSr2La2 trigonal pyramids, an edgeedge with one OSrLa3 tetrahedra, and edges with two OSr2La2 trigonal pyramids. In the fourth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 trigonal pyramids that share corners with five OSrLa3 tetrahedra, a cornercorner with one OSr2La3 trigonal bipyramid, corners with two OSr2La2 trigonal pyramids, and an edgeedge with one OSr2La2 trigonal pyramid. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three La3+ atoms. In the sixth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 trigonal pyramids that share corners with four OSrLa3 tetrahedra, a cornercorner with one OSr2La2 trigonal pyramid, an edgeedge with one OSr2La3 trigonal bipyramid, and an edgeedge with one OSr2La2 trigonal pyramid. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two La3+ atoms. In the eighth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 trigonal pyramids that share corners with two OSrLa3 tetrahedra, a cornercorner with one OSr2La3 trigonal bipyramid, a cornercorner with one OSr2La2 trigonal pyramid, and an edgeedge with one OSrLa3 tetrahedra. In the ninth O2- site, O2- is bonded to one Sr2+ and three La3+ atoms to form OSrLa3 tetrahedra that share corners with two OSr2La2 tetrahedra, corners with four OSr2La2 trigonal pyramids, an edgeedge with one OSr2La3 trigonal bipyramid, and an edgeedge with one OSr2La2 trigonal pyramid. In the tenth O2- site, O2- is bonded to one Sr2+ and three La3+ atoms to form distorted OSrLa3 tetrahedra that share a cornercorner with one OSr2La3 trigonal bipyramid, corners with five OSr2La2 trigonal pyramids, and an edgeedge with one OSr2La2 tetrahedra. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to three La3+ atoms. In the twelfth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 trigonal pyramids that share corners with four OSrLa3 tetrahedra, a cornercorner with one OSr2La3 trigonal bipyramid, a cornercorner with one OSr2La2 trigonal pyramid, an edgeedge with one OSr2La3 trigonal bipyramid, and an edgeedge with one OSr2La2 trigonal pyramid. In the thirteenth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 trigonal pyramids that share corners with two equivalent OSrLa3 tetrahedra, a cornercorner with one OSr2La2 trigonal pyramid, edges with two OSr2La2 tetrahedra, and an edgeedge with one OSr2La2 trigonal pyramid. In the fourteenth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form distorted OSr2La2 tetrahedra that share a cornercorner with one OSrLa3 tetrahedra, corners with five OSr2La2 trigonal pyramids, an edgeedge with one OSrLa3 tetrahedra, and an edgeedge with one OSr2La2 trigonal pyramid. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and three La3+ atoms. In the sixteenth O2- site, O2- is bonded to two Sr2+ and two La3+ atoms to form OSr2La2 tetrahedra that share a cornercorner with one OSrLa3 tetrahedra, a cornercorner with one OSr2La3 trigonal bipyramid, corners with three OSr2La2 trigonal pyramids, and an edgeedge with one OSr2La2 trigonal pyramid. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and three La3+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two La3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Lanthanum induced lattice strain improves hydrogen sulfide capacities of copper oxide adsorbents

This work probes the effects of La on reactions involving CuO sorbents and H 2 S in gaseous streams. La-CuO sorbents with nominal La/Cu atomic ratios of 1:2 achieved higher capacities (27 and 36 g H 2 S per 100 g sorbent) compared to CuO sorbents (25 g H 2 S per 100 g sorbent). Here, comparison of the La-CuO sorbents using energy dispersive x-ray spectroscopy and La L 3 -edge XAS suggested that increased capacity resulted from more uniform dispersion of La within the CuO phase (3.3 wt.% vs. 1.0 wt.% La). X-Ray absorption near edge structure analysis suggested more electron-rich Cu species in La-CuO samples, while extended X-ray absorption fine structure modeling showed an increase in single-scattering path lengths for neighboring and near-neighbor atoms. These changes suggest that La induces strain in the Cu-O lattice, thereby increasing H 2 S capacity by reducing energy barriers associated with surface reactions between oxygen atoms and adsorbed H 2 S molecules.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Laser Ablation-Capillary Absorption Spectroscopy: A novel approach for high throughput and increased spatial resolution measurements of δ 13 C in plant-soil systems

Spatial and temporal heterogeneity of nutrient exchange within the rhizosphere is a topic of increasing interest, although challenging to study due to limits in existing analytical capabilities. Here, we developed and demonstrated a new approach applying laser ablation sample introduction to capillary absorption spectroscopy (LA-CAS) to characterize carbon isotopic distribution within plant tissues, rhizosphere, and soil. We exposed switchgrass plants to 13 CO 2 to allow tracing of 13 C-labelled photosynthates within plant biomass and into the associated soil. The LA-CAS methods we describe leverage continuous measurements of a sample stream derived from laser ablation line scans (10-25 µm in width) over a sample surface which enables the user to produce an isotope map with a) higher data density or b) over larger spatial areas versus previously existing techniques. This versatility of LA-CAS is assessed through testing of a range of laser parameters (spot size, scan rates) on various materials (soil, plant biomass/tissues, and rhizosphere). Here, we demonstrate the ability of LA-CAS to provide near instantaneous $δ$ 13 C measurements over isotopically distinct surfaces to enable high spatially resolved mapping of 13 C-labelled material within the rhizosphere. Applying LA-CAS analysis to plant biomass, we observed higher $δ$ 13 C values concentrated within phloem structures, consistent with localized photosynthate transport. When mapping across the rhizosphere, 13 C-enriched soil was typically present within 5-10µm of root boundaries with a steep spatial increase in $δ$ 13 C when the scan approached the middle of the root. As with all LA approaches, care is required to ensure accurate results as phenomena linked to ablation, combustion, and isotopic measurement can impart artifacts if not carefully controlled. Still, taken as a whole, our demonstrations highlight the increased sample throughput, improved data density, and enhanced $δ$ 13 C capability of LA-CAS versus other LA techniques and emphasize the role this method can play in future plant and rhizosphere related studies.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2026

Solid-state NMR and theoretical studies illuminate lanthanum borohydride C–H borylation catalysts confined within a zeolite

Zeolite-supported single-site lanthanum borohydride catalyzes C–H borylation of hydrocarbons, while the related silica-supported complex is inactive under comparable conditions. The identical composition of support-La(BH 4 ) 2 (THF) 2 sites in the two materials implies that the support bestows underlying structural features onto La that are required for bond activation catalysis, yet the nature of these effects, which could include confinement effects and/or electronic modulation of the site itself, remains to be identified. We used solid-state nuclear magnetic resonance (SSNMR) spectroscopy and molecular dynamics simulations with machine-learning potentials (ML-MD) to analyze the electronic and steric effects imparted by the faujasite support on the precatalyst structure to correlate with catalytic activity. ML-MD simulations show that THF dissociates from La under the influence of confinement, leading to coordinatively unsaturated sites in the zeolite pores. Then, the La complex grafts on Brønsted acid sites (La BAS ) or isolated silanols (La SiO ) or remains physisorbed in the zeolite pores. Catalytic studies comparing compounds supported on faujasite zeolites containing or lacking BAS and/or silanols show that only the former complexes lead to active sites, ruling out confinement as the sole requirement for catalysis. The DFT calculations and ML-MD simulations also reveal that the surface-lanthanum coordination number is two (bidentate) for La BAS , with the metal center forming long, flexible bonds to two oxygen atoms bridging Si and Al, but only one oxygen atom (monodentate) for La SiO . The structure–activity relationship identifies confined, BAS-grafted species as active sites and provides important guidance for the design of enhanced atom-efficient catalysts.

Cui, Jinlei [Ames Laboratory, and Iowa State Univ.↗
DOE OSTI2025

Análisis de Tareas del Inspector de Control de Calidad [Quality Control Inspector Job Task Analysis (Spanish Translation)]

El Laboratorio Nacional de Energía Renovable (NREL) ha sido contratado por el Programa de Asistencia para la Climatización (WAP) del Departamento de Energía de EE.UU. (DOE) para desarrollar y mantener los recursos en el marco del proyecto de Directrices para Profesionales de la Energía Doméstica (GHEP). El objetivo del proyecto GHEP es aumentar la calidad del trabajo realizado para la remodelación energética residencial en Estados Unidos a través de WAP y otros programas de remodelación residencial. Para cumplir el objetivo de “Establecer certificaciones nacionales de la mano de obra y normas de formación”, el DOE encargó al NREL el desarrollo de recursos GHEP, incluido un conjunto de certificaciones avanzadas, basadas en aptitud, para el personal de los profesionales de la energía doméstica (HEP). Desde 2010, el NREL ha reclutado voluntarios expertos en la materia de WAP y de la industria del mantenimiento del hogar para que formen parte de comités que desarrollen y actualicen programas de certificación y sus análisis de tareas (JTA) necesarios como base de programas de certificación y formación estandarizados. Las certificaciones HEP apoyan al WAP y al sector del mantenimiento de viviendas residenciales en general mediante el proceso de acreditación y el desarrollo de JTA definidos para auditores energéticos (EA) e inspectores de control de calidad (QCI). Este informe es un resumen de las actualizaciones más recientes (2022) del JTA del QCI. [The National Renewable Energy Laboratory (NREL) is contracted by the U.S. Department of Energy (DOE) Weatherization Assistance Program (WAP) to develop and maintain the resources under the Guidelines for Home Energy Professionals (GHEP) project. The purpose of the GHEP project is to increase the quality of work conducted for residential energy retrofits in the United States through the WAP network and other residential retrofit programs. This is the Spanish translation of NREL/TP-7A40-85789.]

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS2023

Spatial distributions of Tribrachidium, Rugoconites, and Obamus from the Ediacara Member (Rawnsley Quartzite), South Australia

The spatial distribution of in situ sessile organisms, including those from the fossil record, provides information about life histories, such as possible dispersal and/or settlement mechanisms, and how taxa interact with one another and their local environments. At Nilpena Ediacara National Park (NENP), South Australia, the exquisite preservation and excavation of 33 fossiliferous bedding planes from the Ediacara Member of the Rawnsley Quartzite reveals in situ communities of the Ediacara Biota. Here, the spatial distributions of three relatively common taxa, Tribrachidium, Rugoconites, and Obamus, occurring on excavated surfaces were analyzed using spatial point pattern analysis. Tribrachidium have a variable spatial distribution, implying that settlement or post-settlement conditions/preferences had an effect on populations. Rugoconites display aggregation, possibly related to their reproductive methods in combination with settlement location availability at the time of dispersal and/or settlement. Additionally, post-settlement environmental controls could have affected Rugoconites on other surfaces, resulting in lower populations and densities. Both Tribrachidium and Rugoconites also commonly occur as individuals or in low numbers on a number of beds, thus constraining possible reproductive strategies and environmental/substrate preferences. The distribution of Obamus is consistent with selective settlement, aggregating near conspecifics and on substrates of mature microbial mat. This dispersal process is the first example of substrate-selective dispersal among the Ediacara Biota, thus making Obamus similar to numerous modern sessile invertebrates with similar dispersal and settlement strategies. Resumen La distribución espacial de los organismos sésiles in situ, incluyendo los del registro fósil, brinda información sobre las historias de vida, tal como los posibles mecanismos de dispersión y/o asentamiento, y sobre cómo los taxones interactúan entre sí y entre sus entornos locales. En el Parque Nacional Nilpena Ediacara (NENP), Australia Meridional, la excelente preservación y excavación de 33 planos de lecho fosilífero del Miembro Ediacara de la Cuarcita Rawnsley revela comunidades in situ de la biota ediacárica. En este estudio analizamos las distribuciones espaciales de tres taxones relativamente comunes, Tribrachidium, Rugoconites y Obamus, que se encuentran en superficies excavadas mediante el análisis de patrones de puntos espaciales. Tribrachidium tiene una distribución espacial variable, lo que implica que las condiciones/preferencias durante o después del asentamiento tuvieron un efecto en las poblaciones. Rugoconites muestran agregación, posiblemente relacionado con sus métodos reproductivos en combinación con la disponibilidad de lugares de asentamiento en el momento de la dispersión y/o asentamiento. Además, los controles ambientales posteriormente al asentamiento podrían estar afectando a Rugoconites en otras superficies, lo que resultaría en poblaciones y densidades más bajas. Tanto Tribrachidium como Rugoconites ocurren como individuos en varios lechos, restringiendo las posibles estrategias reproductivas y las preferencias ambientales/de sustrato. La distribución de Obamus es consistente con un asentamiento selectivo, agregando cerca de sus congéneres y sobre sustratos de tapete microbiano maduro. Este proceso de dispersión es el primer ejemplo de dispersión selectiva de sustrato entre la biota ediacárica, lo que hace que Obamus sea similar a numerosos invertebrados sésiles modernos con estrategias similares de dispersión y asentamiento.

Phillip C. Boan↗