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At least 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Tb7RhBr12 by Materials Project

Tb7RhBr12 is trigonal omega-derived structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded to one Rh and five Br atoms to form a mixture of corner and edge-sharing TbRhBr5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The Tb–Rh bond length is 2.68 Å. There are a spread of Tb–Br bond distances ranging from 2.91–3.14 Å. In the second Tb site, Tb is bonded to six equivalent Br atoms to form edge-sharing TbBr6 octahedra. All Tb–Br bond lengths are 2.83 Å. Rh is bonded in an octahedral geometry to six equivalent Tb atoms. There are two inequivalent Br sites. In the first Br site, Br is bonded in a T-shaped geometry to three equivalent Tb atoms. In the second Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pb4Br3NO16 by Materials Project

Pb4NO16Br3 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Pb3+ sites. In the first Pb3+ site, Pb3+ is bonded in a 6-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.34–3.04 Å. In the second Pb3+ site, Pb3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Pb–O bond distances ranging from 2.33–2.87 Å. In the third Pb3+ site, Pb3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.34–3.02 Å. In the fourth Pb3+ site, Pb3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.30–3.08 Å. N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.26 Å) and one longer (1.27 Å) N–O bond length. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Pb3+ and one Br5+ atom. The O–Br bond length is 1.72 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one Br5+ atom. The O–Br bond length is 1.70 Å. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one Br5+ atom. The O–Br bond length is 1.67 Å. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one Br5+ atom. The O–Br bond length is 1.70 Å. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one Br5+ atom. The O–Br bond length is 1.70 Å. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Pb3+ and one Br5+ atom. The O–Br bond length is 1.68 Å. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Pb3+ and one Br5+ atom. The O–Br bond length is 1.70 Å. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Pb3+ and one Br5+ atom. The O–Br bond length is 1.72 Å. In the ninth O2- site, O2- is bonded in a single-bond geometry to one Br5+ atom. The O–Br bond length is 1.67 Å. In the tenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Pb3+ atoms. In the eleventh O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Pb3+ atoms. In the twelfth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Pb3+ atoms. In the thirteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Pb3+ atoms. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one Pb3+ and one N5+ atom. In the fifteenth O2- site, O2- is bonded in a single-bond geometry to one Pb3+ and one N5+ atom. In the sixteenth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. There are three inequivalent Br5+ sites. In the first Br5+ site, Br5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. In the second Br5+ site, Br5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. In the third Br5+ site, Br5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KTmBr3 by Materials Project

KTmBr3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K is bonded in a 8-coordinate geometry to eight Br atoms. There are a spread of K–Br bond distances ranging from 3.34–3.81 Å. Tm is bonded to six Br atoms to form corner-sharing TmBr6 octahedra. The corner-sharing octahedra tilt angles range from 29–32°. There are four shorter (2.84 Å) and two longer (2.85 Å) Tm–Br bond lengths. There are two inequivalent Br sites. In the first Br site, Br is bonded in a 5-coordinate geometry to three equivalent K and two equivalent Tm atoms. In the second Br site, Br is bonded to two equivalent K and two equivalent Tm atoms to form distorted corner-sharing BrK2Tm2 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KAu(Br2O)2 by Materials Project

KAu(OBr2)2 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two KAu(OBr2)2 ribbons oriented in the (1, 0, 1) direction. K1+ is bonded in a linear geometry to two equivalent O2- atoms. Both K–O bond lengths are 2.61 Å. Au1+ is bonded in a square co-planar geometry to four Br+0.50+ atoms. There are two shorter (2.47 Å) and two longer (2.60 Å) Au–Br bond lengths. O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and one Br+0.50+ atom. The O–Br bond length is 1.74 Å. There are two inequivalent Br+0.50+ sites. In the first Br+0.50+ site, Br+0.50+ is bonded in a single-bond geometry to one Au1+ atom. In the second Br+0.50+ site, Br+0.50+ is bonded in a bent 120 degrees geometry to one Au1+ and one O2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KAu(Br2O)2 by Materials Project

KAu(OBr2)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two KAu(OBr2)2 sheets oriented in the (0, 1, 0) direction. K1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. There are two shorter (2.72 Å) and two longer (2.88 Å) K–O bond lengths. Au1+ is bonded in a square co-planar geometry to four Br+0.50+ atoms. There are two shorter (2.46 Å) and two longer (2.59 Å) Au–Br bond lengths. O2- is bonded in a trigonal non-coplanar geometry to two equivalent K1+ and one Br+0.50+ atom. The O–Br bond length is 1.74 Å. There are two inequivalent Br+0.50+ sites. In the first Br+0.50+ site, Br+0.50+ is bonded in a single-bond geometry to one Au1+ atom. In the second Br+0.50+ site, Br+0.50+ is bonded in a distorted water-like geometry to one Au1+ and one O2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Er4OsBr4 by Materials Project

Er4OsBr4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded to two equivalent Os and four Br atoms to form a mixture of distorted edge, face, and corner-sharing ErOs2Br4 pentagonal pyramids. There are one shorter (2.87 Å) and one longer (2.88 Å) Er–Os bond lengths. There are a spread of Er–Br bond distances ranging from 2.96–3.12 Å. In the second Er site, Er is bonded to two equivalent Os and four Br atoms to form a mixture of distorted edge, face, and corner-sharing ErOs2Br4 pentagonal pyramids. There are one shorter (2.87 Å) and one longer (2.88 Å) Er–Os bond lengths. There are a spread of Er–Br bond distances ranging from 2.95–3.09 Å. Os is bonded in a 8-coordinate geometry to eight Er atoms. There are two inequivalent Br sites. In the first Br site, Br is bonded in a 4-coordinate geometry to four Er atoms. In the second Br site, Br is bonded in a 4-coordinate geometry to four Er atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaBr2O by Materials Project

BaOBr2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba is bonded in a 2-coordinate geometry to two equivalent O and four equivalent Br atoms. Both Ba–O bond lengths are 2.67 Å. There are one shorter (3.29 Å) and three longer (3.41 Å) Ba–Br bond lengths. O is bonded in a trigonal planar geometry to two equivalent Ba and one Br atom. The O–Br bond length is 1.83 Å. There are two inequivalent Br sites. In the first Br site, Br is bonded in a distorted single-bond geometry to one O atom. In the second Br site, Br is bonded to four equivalent Ba atoms to form a mixture of corner and edge-sharing BrBa4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbDyBr3 by Materials Project

RbDyBr3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Rb is bonded in a 8-coordinate geometry to eight Br atoms. There are a spread of Rb–Br bond distances ranging from 3.53–3.87 Å. Dy is bonded to six Br atoms to form corner-sharing DyBr6 octahedra. The corner-sharing octahedra tilt angles range from 24–25°. All Dy–Br bond lengths are 2.88 Å. There are two inequivalent Br sites. In the first Br site, Br is bonded in a 5-coordinate geometry to three equivalent Rb and two equivalent Dy atoms. In the second Br site, Br is bonded in a distorted square co-planar geometry to two equivalent Rb and two equivalent Dy atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlBr3N by Materials Project

AlNBr3 is Silicon tetrafluoride-derived structured and crystallizes in the orthorhombic Pbca space group. The structure is zero-dimensional and consists of sixteen AlNBr3 clusters. Al is bonded in a trigonal pyramidal geometry to one N and three Br atoms. The Al–N bond length is 2.02 Å. There are one shorter (2.27 Å) and two longer (2.29 Å) Al–Br bond lengths. N is bonded in a single-bond geometry to one Al atom. There are three inequivalent Br sites. In the first Br site, Br is bonded in a single-bond geometry to one Al atom. In the second Br site, Br is bonded in a single-bond geometry to one Al atom. In the third Br site, Br is bonded in a single-bond geometry to one Al atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaH2BrO5 by Materials Project

NaH2O5Br crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to six O atoms to form NaO6 octahedra that share corners with four equivalent BrO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.35–2.49 Å. In the second Na site, Na is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.32 Å) and two longer (2.38 Å) Na–O bond lengths. There are two inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.97 Å. In the second H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. There are five inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Na, one H, and one O atom. The O–O bond length is 1.47 Å. In the second O site, O is bonded in a bent 150 degrees geometry to one Na and one Br atom. The O–Br bond length is 1.65 Å. In the third O site, O is bonded in a bent 120 degrees geometry to one Na and one Br atom. The O–Br bond length is 1.66 Å. In the fourth O site, O is bonded in a distorted single-bond geometry to one Na, one H, and one Br atom. The O–Br bond length is 2.06 Å. In the fifth O site, O is bonded in a 3-coordinate geometry to one Na, one O, and one Br atom. The O–Br bond length is 2.15 Å. Br is bonded to four O atoms to form distorted BrO4 tetrahedra that share corners with two equivalent NaO6 octahedra. The corner-sharing octahedra tilt angles range from 28–29°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsDyBr3 by Materials Project

CsDyBr3 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Cs is bonded to twelve Br atoms to form distorted CsBr12 cuboctahedra that share corners with twelve equivalent CsBr12 cuboctahedra, faces with six equivalent CsBr12 cuboctahedra, and faces with eight equivalent DyBr6 octahedra. There are a spread of Cs–Br bond distances ranging from 3.80–4.27 Å. Dy is bonded to six Br atoms to form DyBr6 octahedra that share corners with six equivalent DyBr6 octahedra and faces with eight equivalent CsBr12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are four shorter (2.85 Å) and two longer (2.86 Å) Dy–Br bond lengths. There are two inequivalent Br sites. In the first Br site, Br is bonded in a distorted linear geometry to four equivalent Cs and two equivalent Dy atoms. In the second Br site, Br is bonded in a 2-coordinate geometry to four equivalent Cs and two equivalent Dy atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsMnBr3O2 by Materials Project

CsMnO2Br3 crystallizes in the orthorhombic Pcca space group. The structure is three-dimensional. Cs is bonded to four equivalent O and eight Br atoms to form CsBr8O4 cuboctahedra that share corners with two equivalent CsBr8O4 cuboctahedra, corners with two equivalent MnBr4O2 octahedra, edges with four equivalent CsBr8O4 cuboctahedra, faces with two equivalent CsBr8O4 cuboctahedra, and faces with four equivalent MnBr4O2 octahedra. The corner-sharing octahedral tilt angles are 18°. There are two shorter (3.38 Å) and two longer (3.55 Å) Cs–O bond lengths. There are a spread of Cs–Br bond distances ranging from 3.69–4.10 Å. Mn is bonded to two equivalent O and four Br atoms to form distorted MnBr4O2 octahedra that share corners with two equivalent CsBr8O4 cuboctahedra, corners with two equivalent MnBr4O2 octahedra, and faces with four equivalent CsBr8O4 cuboctahedra. The corner-sharing octahedral tilt angles are 69°. Both Mn–O bond lengths are 2.08 Å. There are two shorter (2.48 Å) and two longer (2.73 Å) Mn–Br bond lengths. O is bonded in a 4-coordinate geometry to two equivalent Cs, one Mn, and one O atom. The O–O bond length is 1.31 Å. There are two inequivalent Br sites. In the first Br site, Br is bonded in a distorted single-bond geometry to three equivalent Cs and one Mn atom. In the second Br site, Br is bonded in a distorted see-saw-like geometry to two equivalent Cs and two equivalent Mn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaBr2O by Materials Project

BaOBr2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba is bonded in a 2-coordinate geometry to two equivalent O and seven Br atoms. Both Ba–O bond lengths are 2.72 Å. There are a spread of Ba–Br bond distances ranging from 3.35–3.44 Å. O is bonded in a distorted bent 150 degrees geometry to two equivalent Ba and two Br atoms. There are one shorter (2.56 Å) and one longer (2.62 Å) O–Br bond lengths. There are two inequivalent Br sites. In the first Br site, Br is bonded in a 4-coordinate geometry to three equivalent Ba and one O atom. In the second Br site, Br is bonded in a 5-coordinate geometry to four equivalent Ba and one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaBr2O11 by Materials Project

BaO11Br2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Ba is bonded to twelve O atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent BrO4 tetrahedra and faces with two equivalent BaO12 cuboctahedra. There are a spread of Ba–O bond distances ranging from 2.79–3.12 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Br atom. The O–Br bond length is 1.63 Å. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Ba and one Br atom. The O–Br bond length is 1.66 Å. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one Ba and one Br atom. The O–Br bond length is 1.66 Å. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to one Ba and one Br atom. The O–Br bond length is 1.66 Å. In the fifth O site, O is bonded in a 4-coordinate geometry to two equivalent Ba and two O atoms. There is one shorter (1.46 Å) and one longer (1.47 Å) O–O bond length. In the sixth O site, O is bonded in a 4-coordinate geometry to two equivalent Ba and two O atoms. The O–O bond length is 1.47 Å. In the seventh O site, O is bonded in a 4-coordinate geometry to two equivalent Ba and two O atoms. Br is bonded to four O atoms to form BrO4 tetrahedra that share corners with three equivalent BaO12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg11I2BrClO4 by Materials Project

Hg11O4I2BrCl crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eleven inequivalent Hg+1.09+ sites. In the first Hg+1.09+ site, Hg+1.09+ is bonded in a distorted L-shaped geometry to two O2-, two I1-, and one Br1- atom. There are one shorter (2.22 Å) and one longer (2.77 Å) Hg–O bond lengths. There are one shorter (3.55 Å) and one longer (3.79 Å) Hg–I bond lengths. The Hg–Br bond length is 3.48 Å. In the second Hg+1.09+ site, Hg+1.09+ is bonded in a distorted L-shaped geometry to two O2-, two I1-, and one Cl1- atom. There are one shorter (2.21 Å) and one longer (2.76 Å) Hg–O bond lengths. There are one shorter (3.57 Å) and one longer (3.78 Å) Hg–I bond lengths. The Hg–Cl bond length is 3.44 Å. In the third Hg+1.09+ site, Hg+1.09+ is bonded in a distorted single-bond geometry to one O2-, one I1-, and one Br1- atom. The Hg–O bond length is 2.19 Å. The Hg–I bond length is 3.33 Å. The Hg–Br bond length is 3.07 Å. In the fourth Hg+1.09+ site, Hg+1.09+ is bonded in a distorted single-bond geometry to one O2-, one I1-, and one Cl1- atom. The Hg–O bond length is 2.18 Å. The Hg–I bond length is 3.37 Å. The Hg–Cl bond length is 2.98 Å. In the fifth Hg+1.09+ site, Hg+1.09+ is bonded in a distorted L-shaped geometry to two O2-, one Br1-, and one Cl1- atom. There are one shorter (2.23 Å) and one longer (2.61 Å) Hg–O bond lengths. The Hg–Br bond length is 3.68 Å. The Hg–Cl bond length is 3.21 Å. In the sixth Hg+1.09+ site, Hg+1.09+ is bonded in a distorted L-shaped geometry to two O2- and one Br1- atom. There are one shorter (2.23 Å) and one longer (2.62 Å) Hg–O bond lengths. The Hg–Br bond length is 3.30 Å. In the seventh Hg+1.09+ site, Hg+1.09+ is bonded in a linear geometry to two O2-, two I1-, and one Br1- atom. Both Hg–O bond lengths are 2.08 Å. There are one shorter (3.34 Å) and one longer (3.35 Å) Hg–I bond lengths. The Hg–Br bond length is 3.66 Å. In the eighth Hg+1.09+ site, Hg+1.09+ is bonded in a distorted single-bond geometry to one O2-, one Br1-, and one Cl1- atom. The Hg–O bond length is 2.18 Å. The Hg–Br bond length is 3.61 Å. The Hg–Cl bond length is 3.09 Å. In the ninth Hg+1.09+ site, Hg+1.09+ is bonded in a distorted single-bond geometry to one O2- and one Br1- atom. The Hg–O bond length is 2.20 Å. The Hg–Br bond length is 3.14 Å. In the tenth Hg+1.09+ site, Hg+1.09+ is bonded in a single-bond geometry to one O2-, three I1-, and one Cl1- atom. The Hg–O bond length is 2.22 Å. There are a spread of Hg–I bond distances ranging from 3.44–3.59 Å. The Hg–Cl bond length is 3.41 Å. In the eleventh Hg+1.09+ site, Hg+1.09+ is bonded in a single-bond geometry to one O2-, three I1-, and one Br1- atom. The Hg–O bond length is 2.22 Å. There are a spread of Hg–I bond distances ranging from 3.44–3.57 Å. The Hg–Br bond length is 3.40 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Hg+1.09+ atoms to form distorted edge-sharing OHg4 tetrahedra. In the second O2- site, O2- is bonded to four Hg+1.09+ and one Br1- atom to form distorted edge-sharing OHg4Br tetrahedra. The O–Br bond length is 3.36 Å. In the third O2- site, O2- is bonded to four Hg+1.09+ and one I1- atom to form a mixture of distorted edge and corner-sharing OHg4I tetrahedra. The O–I bond length is 3.56 Å. In the fourth O2- site, O2- is bonded to four Hg+1.09+ and one I1- atom to form a mixture of distorted edge and corner-sharing OHg4I tetrahedra. The O–I bond length is 3.57 Å. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 8-coordinate geometry to seven Hg+1.09+ and one O2- atom. In the second I1- site, I1- is bonded in a 6-coordinate geometry to seven Hg+1.09+ and one O2- atom. Br1- is bonded in a 2-coordinate geometry to eight Hg+1.09+ and one O2- atom. Cl1- is bonded in a 2-coordinate geometry to five Hg+1.09+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr20P12Br3O48F by Materials Project

Sr20P12O48Br3F crystallizes in the trigonal P-3 space group. The structure is three-dimensional. there are six inequivalent Sr sites. In the first Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are six shorter (2.59 Å) and three longer (2.93 Å) Sr–O bond lengths. In the second Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sr–O bond distances ranging from 2.58–2.96 Å. In the third Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sr–O bond distances ranging from 2.59–2.92 Å. In the fourth Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are six shorter (2.59 Å) and three longer (2.93 Å) Sr–O bond lengths. In the fifth Sr site, Sr is bonded in a 3-coordinate geometry to six O and two Br atoms. There are a spread of Sr–O bond distances ranging from 2.43–3.06 Å. There are one shorter (3.18 Å) and one longer (3.21 Å) Sr–Br bond lengths. In the sixth Sr site, Sr is bonded in a 8-coordinate geometry to six O, one Br, and one F atom. There are a spread of Sr–O bond distances ranging from 2.48–3.08 Å. The Sr–Br bond length is 3.12 Å. The Sr–F bond length is 3.07 Å. There are two inequivalent P sites. In the first P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. In the second P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to three Sr and one P atom. In the second O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom. In the third O site, O is bonded in a 4-coordinate geometry to three Sr and one P atom. In the fourth O site, O is bonded in a 4-coordinate geometry to three Sr and one P atom. In the fifth O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom. In the sixth O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom. In the seventh O site, O is bonded in a distorted single-bond geometry to three Sr and one P atom. In the eighth O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom. There are two inequivalent Br sites. In the first Br site, Br is bonded to six Sr atoms to form BrSr6 octahedra that share a faceface with one BrSr6 octahedra and a faceface with one FSr6 octahedra. In the second Br site, Br is bonded to six equivalent Sr atoms to form face-sharing BrSr6 octahedra. F is bonded to six equivalent Sr atoms to form FSr6 octahedra that share faces with two equivalent BrSr6 octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Unveiling the role of halide mixing in the crystallization kinetics and charge transfer mechanisms of wide-bandgap organic–inorganic halide perovskites

Understanding the crystallization kinetics of Br–I mixed-halide WBG perovskite films, and their correlation to the crystallographic structure and charge transfer dynamics, is critical for advancing WBG perovskite devices. Despite many efforts to increase the photovoltaic performances of wide-bandgap (WBG, with a Br content above 20%) perovskite solar cells based on bromine–iodine (Br–I) mixed-halide perovskites, understanding the crystallization kinetics of WBG perovskite films, as well as the role of Br mixing in the crystallization kinetics, is still lacking. Furthermore, an overlooked aspect is the correlation of the halide compositions, crystallization kinetics, crystallographic structure, and charge transfer dynamics. Here, we unveil that Br–I mixed-halide WBG perovskite films undergo two intrinsically different crystallization kinetic processes. One is the intermediate solvent-complex phase-assisted growth (I-rich), and the other is top-to-bottom downward growth (Br-rich). Such downward growth (including high Br concentrations) correlates with the formation of a highly vertically oriented perovskite film, which is accompanied by defect formation caused by a dissolving and recrystallization process coupled with halide homogenization. Consequently, Br-rich WBG perovskite films exhibit enhanced charge carrier transport, but are concurrently plagued by non-radiative charge recombination. Addressing this fundamental perspective is critical to precisely tailor Br-related crystallization, which significantly affects the structure and optoelectronic properties of WBG perovskite films and devices.

Li, Nian↗
DOE OSTI2024

A maize semi-dwarf mutant reveals a GRAS transcription factor involved in brassinosteroid signaling

Brassinosteroids (BR) and gibberellins (GA) regulate plant height and leaf angle in maize (Zea mays). Mutants with defects in BR or GA biosynthesis or signaling identify components of these pathways and enhance our knowledge about plant growth and development. In this study, we characterized three recessive mutant alleles of GRAS transcription factor 42 (gras42) in maize, a GRAS transcription factor gene orthologous to the DWARF AND LOW TILLERING (DLT) gene of rice (Oryza sativa). These maize mutants exhibited semi-dwarf stature, shorter and wider leaves, and more upright leaf angle. Transcriptome analysis revealed a role for GRAS42 as a determinant of BR signaling. Analysis of the expression consequences from loss of GRAS42 in the gras42-mu1021149 mutant indicated a weak loss of BR signaling in the mutant, consistent with its previously demonstrated role in BR signaling in rice. Loss of BR signaling was also evident by the enhancement of weak BR biosynthetic mutant alleles in double mutants of nana plant1-1 and gras42-mu1021149. The gras42-mu1021149 mutant had little effect on GA-regulated gene expression, suggesting that GRAS42 is not a regulator of core GA signaling genes in maize. Single-cell expression data identified gras42 expressed among cells in the G2/M phase of the cell cycle consistent with its previously demonstrated role in cell cycle gene expression in Arabidopsis (Arabidopsis thaliana). Cis-acting natural variation controlling GRAS42 transcript accumulation was identified by expression genome-wide association study (eGWAS) in maize. Our results demonstrate a conserved role for GRAS42/SCARECROW-LIKE 28 (SCL28)/DLT in BR signaling, clarify the role of this gene in GA signaling, and suggest mechanisms of tillering and leaf angle control by BR.

54 ENVIRONMENTAL SCIENCES↗