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DOE OSTI2020

Materials Data on BaYCo2O5 by Materials Project

YBaCo2O5 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four equivalent CoO5 square pyramids, and faces with four equivalent CoO5 trigonal bipyramids. There are a spread of Ba–O bond distances ranging from 2.79–3.09 Å. Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.42 Å) and six longer (2.43 Å) Y–O bond lengths. There are two inequivalent Co+2.50+ sites. In the first Co+2.50+ site, Co+2.50+ is bonded to five O2- atoms to form CoO5 square pyramids that share corners with two equivalent CoO5 square pyramids, corners with three equivalent CoO5 trigonal bipyramids, and faces with four equivalent BaO12 cuboctahedra. There are a spread of Co–O bond distances ranging from 2.00–2.13 Å. In the second Co+2.50+ site, Co+2.50+ is bonded to five O2- atoms to form distorted CoO5 trigonal bipyramids that share corners with three equivalent CoO5 square pyramids, corners with two equivalent CoO5 trigonal bipyramids, and faces with four equivalent BaO12 cuboctahedra. There are a spread of Co–O bond distances ranging from 1.82–2.04 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Co+2.50+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two Co+2.50+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Co+2.50+ atoms. In the fourth O2- site, O2- is bonded to four equivalent Ba2+ and two Co+2.50+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V18P9C2 by Materials Project

V18C2P9 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are twelve inequivalent V sites. In the first V site, V is bonded in a distorted square co-planar geometry to four P atoms. There are two shorter (2.45 Å) and two longer (2.51 Å) V–P bond lengths. In the second V site, V is bonded in a 5-coordinate geometry to five P atoms. There are a spread of V–P bond distances ranging from 2.43–2.69 Å. In the third V site, V is bonded in a distorted square co-planar geometry to four P atoms. There are two shorter (2.37 Å) and two longer (2.58 Å) V–P bond lengths. In the fourth V site, V is bonded in a 4-coordinate geometry to four P atoms. There are two shorter (2.33 Å) and two longer (2.49 Å) V–P bond lengths. In the fifth V site, V is bonded in a distorted single-bond geometry to one C and four equivalent P atoms. The V–C bond length is 1.96 Å. All V–P bond lengths are 2.47 Å. In the sixth V site, V is bonded in a 3-coordinate geometry to three C and two equivalent P atoms. There are one shorter (1.99 Å) and two longer (2.08 Å) V–C bond lengths. Both V–P bond lengths are 2.59 Å. In the seventh V site, V is bonded in a 2-coordinate geometry to two equivalent C and three P atoms. Both V–C bond lengths are 2.08 Å. There are two shorter (2.52 Å) and one longer (2.63 Å) V–P bond lengths. In the eighth V site, V is bonded in a 1-coordinate geometry to one C and four P atoms. The V–C bond length is 2.00 Å. There are two shorter (2.41 Å) and two longer (2.45 Å) V–P bond lengths. In the ninth V site, V is bonded to five P atoms to form a mixture of distorted edge, face, and corner-sharing VP5 trigonal bipyramids. There are a spread of V–P bond distances ranging from 2.34–2.43 Å. In the tenth V site, V is bonded to five P atoms to form a mixture of distorted edge, face, and corner-sharing VP5 trigonal bipyramids. There are a spread of V–P bond distances ranging from 2.29–2.38 Å. In the eleventh V site, V is bonded in a 2-coordinate geometry to two equivalent C and three P atoms. Both V–C bond lengths are 2.10 Å. There are two shorter (2.41 Å) and one longer (2.51 Å) V–P bond lengths. In the twelfth V site, V is bonded in a 4-coordinate geometry to five P atoms. There are a spread of V–P bond distances ranging from 2.40–2.80 Å. There are two inequivalent C sites. In the first C site, C is bonded to six V atoms to form a mixture of edge and corner-sharing CV6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second C site, C is bonded to six V atoms to form a mixture of edge and corner-sharing CV6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are five inequivalent P sites. In the first P site, P is bonded in a 9-coordinate geometry to nine V atoms. In the second P site, P is bonded to seven V atoms to form a mixture of distorted edge and corner-sharing PV7 pentagonal bipyramids. In the third P site, P is bonded in a 9-coordinate geometry to nine V atoms. In the fourth P site, P is bonded in a 8-coordinate geometry to eight V atoms. In the fifth P site, P is bonded in a 9-coordinate geometry to nine V atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3Li6Nb2O11 by Materials Project

Li6Sr3Nb2O11 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with two equivalent LiO5 trigonal bipyramids, corners with two equivalent NbO5 trigonal bipyramids, an edgeedge with one NbO6 octahedra, and an edgeedge with one LiO4 tetrahedra. There are two shorter (2.03 Å) and two longer (2.09 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with three LiO4 tetrahedra, a cornercorner with one NbO5 trigonal bipyramid, edges with two equivalent NbO6 octahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO5 trigonal bipyramid. There are three shorter (2.12 Å) and two longer (2.23 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent NbO6 octahedra, corners with three LiO4 tetrahedra, a cornercorner with one LiO5 trigonal bipyramid, corners with two equivalent NbO5 trigonal bipyramids, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 14°. There are a spread of Li–O bond distances ranging from 1.83–2.06 Å. There are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.81 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.49–2.76 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to five O2- atoms to form NbO5 trigonal bipyramids that share corners with eight LiO4 tetrahedra and corners with two equivalent LiO5 trigonal bipyramids. There are a spread of Nb–O bond distances ranging from 1.88–2.03 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four equivalent LiO4 tetrahedra, edges with two equivalent LiO4 tetrahedra, and edges with four equivalent LiO5 trigonal bipyramids. There are two shorter (2.02 Å) and four longer (2.05 Å) Nb–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+, two equivalent Sr2+, and one Nb5+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Li1+, three Sr2+, and one Nb5+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two Li1+, three Sr2+, and one Nb5+ atom. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to three Li1+, two Sr2+, and one Nb5+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Li1+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2Ca3N6 by Materials Project

Li2Ca3N6 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six N+1.33- atoms to form distorted face-sharing LiN6 octahedra. There are a spread of Li–N bond distances ranging from 2.13–2.56 Å. In the second Li1+ site, Li1+ is bonded to six N+1.33- atoms to form distorted face-sharing LiN6 octahedra. There are a spread of Li–N bond distances ranging from 2.10–2.47 Å. There are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight N+1.33- atoms. There are a spread of Ca–N bond distances ranging from 2.46–2.58 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight N+1.33- atoms. There are a spread of Ca–N bond distances ranging from 2.45–2.59 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight N+1.33- atoms. There are a spread of Ca–N bond distances ranging from 2.37–2.65 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight N+1.33- atoms. There are a spread of Ca–N bond distances ranging from 2.36–2.64 Å. There are six inequivalent N+1.33- sites. In the first N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom. The N–N bond length is 1.31 Å. In the second N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom. The N–N bond length is 1.31 Å. In the third N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom. The N–N bond length is 1.32 Å. In the fourth N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom. The N–N bond length is 1.30 Å. In the fifth N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom. In the sixth N+1.33- site, N+1.33- is bonded in a 7-coordinate geometry to two equivalent Li1+, four Ca2+, and one N+1.33- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on DyInCo2 by Materials Project

DyCo2In crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Dy is bonded in a 1-coordinate geometry to seven Co and six equivalent In atoms. There are a spread of Dy–Co bond distances ranging from 2.65–3.10 Å. There are four shorter (3.25 Å) and two longer (3.31 Å) Dy–In bond lengths. There are two inequivalent Co sites. In the first Co site, Co is bonded to four equivalent Dy, six Co, and two equivalent In atoms to form a mixture of corner, edge, and face-sharing CoDy4In2Co6 cuboctahedra. There are four shorter (2.45 Å) and two longer (2.50 Å) Co–Co bond lengths. Both Co–In bond lengths are 2.81 Å. In the second Co site, Co is bonded in a 3-coordinate geometry to three equivalent Dy, four equivalent Co, and two equivalent In atoms. Both Co–In bond lengths are 2.74 Å. In is bonded in a 12-coordinate geometry to six equivalent Dy, four Co, and two equivalent In atoms. Both In–In bond lengths are 3.28 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ti(FeO2)2 by Materials Project

Fe2TiO4 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent TiO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with three equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–51°. There are a spread of Ti–O bond distances ranging from 1.96–2.08 Å. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are four shorter (2.20 Å) and two longer (2.23 Å) Fe–O bond lengths. In the second Fe2+ site, Fe2+ is bonded in a 2-coordinate geometry to eight O2- atoms. There are a spread of Fe–O bond distances ranging from 2.06–2.72 Å. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–55°. There are a spread of Fe–O bond distances ranging from 1.97–2.22 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a square co-planar geometry to four equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a distorted square co-planar geometry to six Fe2+ atoms. In the third O2- site, O2- is bonded to two equivalent Ti4+ and two equivalent Fe2+ atoms to form distorted OTi2Fe2 tetrahedra that share corners with four equivalent OTi2Fe3 square pyramids, corners with two equivalent OTi2Fe2 tetrahedra, corners with six equivalent OTiFe4 trigonal bipyramids, and edges with two equivalent OTiFe4 trigonal bipyramids. In the fourth O2- site, O2- is bonded to four Fe2+ atoms to form OFe4 tetrahedra that share corners with six equivalent OTi2Fe3 square pyramids, corners with two equivalent OFe4 tetrahedra, corners with four equivalent OTiFe4 trigonal bipyramids, and edges with two equivalent OTi2Fe3 square pyramids. In the fifth O2- site, O2- is bonded to one Ti4+ and four Fe2+ atoms to form distorted OTiFe4 trigonal bipyramids that share corners with five OTi2Fe2 tetrahedra, corners with two equivalent OTiFe4 trigonal bipyramids, edges with two equivalent OTi2Fe3 square pyramids, an edgeedge with one OTi2Fe2 tetrahedra, and edges with three equivalent OTiFe4 trigonal bipyramids. In the sixth O2- site, O2- is bonded to two equivalent Ti4+ and three Fe2+ atoms to form distorted OTi2Fe3 square pyramids that share corners with two equivalent OTi2Fe3 square pyramids, corners with five OTi2Fe2 tetrahedra, edges with three equivalent OTi2Fe3 square pyramids, an edgeedge with one OFe4 tetrahedra, and edges with two equivalent OTiFe4 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaMg by Materials Project

MgCa is Tetraauricupride structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Ca is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. There are a spread of Ca–Mg bond distances ranging from 3.43–3.45 Å. Mg is bonded in a body-centered cubic geometry to eight equivalent Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta3O8 by Materials Project

Ta3O8 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are four inequivalent Ta sites. In the first Ta site, Ta is bonded to seven O atoms to form TaO7 pentagonal bipyramids that share corners with two equivalent TaO7 pentagonal bipyramids and edges with five TaO6 octahedra. There are a spread of Ta–O bond distances ranging from 1.96–2.14 Å. In the second Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 5–36°. There are a spread of Ta–O bond distances ranging from 1.93–2.12 Å. In the third Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–36°. There are a spread of Ta–O bond distances ranging from 1.93–2.14 Å. In the fourth Ta site, Ta is bonded to six O atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 4–36°. There are a spread of Ta–O bond distances ranging from 1.91–2.07 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the second O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the third O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the fourth O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Ta atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to three Ta atoms. In the seventh O site, O is bonded in a distorted trigonal planar geometry to three Ta atoms. In the eighth O site, O is bonded in a bent 150 degrees geometry to two Ta atoms. In the ninth O site, O is bonded in a linear geometry to two equivalent Ta atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiMnF3 by Materials Project

LiMnF3 is Marcasite-derived structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Li1+ is bonded to four F1- atoms to form distorted LiF4 tetrahedra that share corners with eight equivalent MnF6 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–73°. There is two shorter (1.93 Å) and two longer (1.99 Å) Li–F bond length. Mn2+ is bonded to six F1- atoms to form MnF6 octahedra that share corners with two equivalent MnF6 octahedra, corners with eight equivalent LiF4 tetrahedra, and edges with two equivalent MnF6 octahedra. The corner-sharing octahedral tilt angles are 62°. There are four shorter (2.12 Å) and two longer (2.24 Å) Mn–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two equivalent Mn2+ atoms. In the second F1- site, F1- is bonded to two equivalent Li1+ and two equivalent Mn2+ atoms to form corner-sharing FLi2Mn2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgAl by Materials Project

MgAl is beta-prime cadmium gold structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Mg is bonded to four equivalent Mg and eight equivalent Al atoms to form a mixture of distorted corner, edge, and face-sharing MgMg4Al8 cuboctahedra. There are two shorter (3.02 Å) and two longer (3.13 Å) Mg–Mg bond lengths. There are a spread of Mg–Al bond distances ranging from 2.94–3.09 Å. Al is bonded in a 12-coordinate geometry to eight equivalent Mg and two equivalent Al atoms. Both Al–Al bond lengths are 2.92 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y3H by Materials Project

Y3H crystallizes in the orthorhombic Pmma space group. The structure is two-dimensional and consists of two Y3H sheets oriented in the (0, 0, 1) direction. there are four inequivalent Y sites. In the first Y site, Y is bonded in a single-bond geometry to two equivalent Y and one H atom. Both Y–Y bond lengths are 3.51 Å. The Y–H bond length is 2.19 Å. In the second Y site, Y is bonded in a linear geometry to four equivalent Y and two equivalent H atoms. There are two shorter (3.65 Å) and two longer (3.70 Å) Y–Y bond lengths. Both Y–H bond lengths are 2.26 Å. In the third Y site, Y is bonded in a bent 120 degrees geometry to one Y and two equivalent H atoms. The Y–Y bond length is 3.61 Å. Both Y–H bond lengths are 2.20 Å. In the fourth Y site, Y is bonded to twelve Y atoms to form YY12 cuboctahedra that share corners with six equivalent YY12 cuboctahedra, edges with two equivalent YY12 cuboctahedra, edges with eight equivalent HY4 tetrahedra, and faces with two equivalent YY12 cuboctahedra. Both Y–Y bond lengths are 3.67 Å. H is bonded to four Y atoms to form HY4 tetrahedra that share corners with three equivalent HY4 tetrahedra and edges with four equivalent YY12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgZr by Materials Project

ZrMg is beta-prime cadmium gold structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Mg is bonded to four equivalent Mg and eight equivalent Zr atoms to form MgMg4Zr8 cuboctahedra that share corners with eight equivalent ZrMg8Zr4 cuboctahedra, corners with ten equivalent MgMg4Zr8 cuboctahedra, edges with six equivalent MgMg4Zr8 cuboctahedra, edges with twelve equivalent ZrMg8Zr4 cuboctahedra, faces with eight equivalent ZrMg8Zr4 cuboctahedra, and faces with twelve equivalent MgMg4Zr8 cuboctahedra. There are two shorter (3.24 Å) and two longer (3.27 Å) Mg–Mg bond lengths. There are six shorter (3.10 Å) and two longer (3.14 Å) Mg–Zr bond lengths. Zr is bonded to eight equivalent Mg and four equivalent Zr atoms to form ZrMg8Zr4 cuboctahedra that share corners with eight equivalent MgMg4Zr8 cuboctahedra, corners with ten equivalent ZrMg8Zr4 cuboctahedra, edges with six equivalent ZrMg8Zr4 cuboctahedra, edges with twelve equivalent MgMg4Zr8 cuboctahedra, faces with eight equivalent MgMg4Zr8 cuboctahedra, and faces with twelve equivalent ZrMg8Zr4 cuboctahedra. There are two shorter (3.27 Å) and two longer (3.28 Å) Zr–Zr bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb2NO4 by Materials Project

(Rb2O2)2N2(O2)2 crystallizes in the orthorhombic Pmma space group. The structure is zero-dimensional and consists of two ammonia molecules, two hydrogen peroxide molecules, and four rubidium hydroxide molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2ClO4 by Materials Project

Y2O4Cl crystallizes in the orthorhombic Pmma space group. The structure is two-dimensional and consists of one Y2O4Cl sheet oriented in the (1, 0, 0) direction. there are two inequivalent Y sites. In the first Y site, Y is bonded in a rectangular see-saw-like geometry to two O and two equivalent Cl atoms. There are one shorter (2.05 Å) and one longer (2.07 Å) Y–O bond lengths. There are one shorter (2.73 Å) and one longer (2.81 Å) Y–Cl bond lengths. In the second Y site, Y is bonded to five O atoms to form distorted edge-sharing YO5 trigonal bipyramids. There are a spread of Y–O bond distances ranging from 2.06–2.74 Å. There are four inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Y and one O atom. The O–O bond length is 1.25 Å. In the second O site, O is bonded in a water-like geometry to two Y atoms. In the third O site, O is bonded in a 3-coordinate geometry to two equivalent Y and one O atom. The O–O bond length is 1.50 Å. In the fourth O site, O is bonded in a water-like geometry to two Y atoms. Cl is bonded in a water-like geometry to two equivalent Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Release of Contaminants from Burning Liquids and Solids

This report details model development, theory, and a literature review focusing on the emission of contaminants on solid substrates in fires. This is the final report from a 2-year Nuclear Safety Research and Development (NSRD) project. The work represents progress towards a goal of having modeling and simulation capabilities that are sufficiently mature and accurate that they can be utilized in place of physical tests for determining safe handling practices. At present, the guidelines for safety are largely empirically based, derived from a survey of existing datasets. This particular report details the development, verification and calibration of a number of code improvements that have been implemented in the SIERRA suite of codes, and the application of those codes to three different experimental scenarios that have been subject of prior tests. The first scenario involves a contaminated PMMA slab, which is exposed to heat. The modeling involved a novel method for simulating the viscous diffusion of the particles in the slab. The second scenario involved a small pool fire of contaminated combustible liquid mimicking historical tests and finds that the release of contaminants has a high functionality with the height of the liquid in the container. The third scenario involves the burning of a contaminated tray of shredded cellulose. A novel release mechanism was formulated based on predicted progress of the decomposition of the cellulose, and while the model was found to result in release that can be tuned to match the experiments, some modifications to the model are desirable to achieve quantitative accuracy.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Amorphous 2D Materials – A Novel Platform for Remote Epitaxy and Nanopatterned Epitaxy of III-V Semiconductors with Low Decomposition Temperatures

III-V semiconductor materials such as indium phosphide (InP) offer outstanding photonic properties that outperforms silicon, but the cost of these wafers is extremely expensive. Although reusing original wafers can effectively minimize the cost, current techniques for wafer recycling of these substrates add significant costs in fabrication, nullifying the cost savings by reusing the wafers. Besides, unlike other III-V materials such as gallium arsenide (GaAs), commonly used epitaxial lift-off method for wafer recycling is not well studied for materials like InP due to lack of lattice-matched sacrificial layers, which makes reusing these wafers more difficult. Remote epitaxy and nanopatterned epitaxy are newly discovered methods that enable single-crystal growth of III-V semiconductor thin films and easy exfoliation of these grown films, thus promising for a new cost-effective pathway of reusing wafers. However, previous methods of transferring two-dimensional (2D) materials, which use polymethyl methacrylate (PMMA) or metal stressor layers to transfer 2D materials grown on foreign substrates like copper (Cu) or silicon carbide (SiC), introduce defects and damages on the 2D layer and/or substrates during the transfer process. Remote epitaxial and nanopatterned epitaxial films grown on the damaged 2D layer/substrate suffer from lower crystal quality and imperfect exfoliation, which undermines wafer reusability and device performance. Here we report the MBE growth of amorphous boron nitride (a-BN) on InP wafers at low temperature that enabled improved quality of remote epitaxial and nanopatterned epitaxial films and their perfect exfoliation. We show fully covered a-BN on InP substrates despite their low decomposition temperatures. The surface of a-BN coated InP substrate remains smooth with a RMS roughness of around 3Â. We also demonstrate 100% coverage of single-crystal InP thin films grown on a-BN, with the film's quality significantly improved compared to the case of transferred 2D materials. In addition, the growth and exfoliation were successfully repeated multiple times, proving the feasibility for InP wafer recycling. Through this low temperature MBE growth approach with remote epitaxy and nanopatterned epitaxy, we successfully demonstrate large-scale flexible thin film exfoliation and recycling of InP substrates, which will lead to new opportunities in InP thin film-based photonics and novel heterostructures with significantly reduced cost.

Lu, Kuangye↗
DOE OSTI2022

Amorphous 2D Materials – A Novel Platform for Remote Epitaxy and Nanopatterned Epitaxy of III-V Semiconductors with Low Decomposition Temperatures

III-V semiconductor materials such as indium phosphide (InP) offer outstanding photonic properties that outperforms silicon, but the cost of these wafers is extremely expensive. Although reusing original wafers can effectively minimize the cost, current techniques for wafer recycling of these substrates add significant costs in fabrication, nullifying the cost savings by reusing the wafers. Besides, unlike other III-V materials such as gallium arsenide (GaAs), commonly used epitaxial lift-off method for wafer recycling is not well studied for materials like InP due to lack of lattice-matched sacrificial layers, which makes reusing these wafers more difficult. Remote epitaxy and nanopatterned epitaxy are newly discovered methods that enable single-crystal growth of III-V semiconductor thin films and easy exfoliation of these grown films, thus promising for a new cost-effective pathway of reusing wafers. However, previous methods of transferring two-dimensional (2D) materials, which use polymethyl methacrylate (PMMA) or metal stressor layers to transfer 2D materials grown on foreign substrates like copper (Cu) or silicon carbide (SiC), introduce defects and damages on the 2D layer and/or substrates during the transfer process. Remote epitaxial and nanopatterned epitaxial films grown on the damaged 2D layer/substrate suffer from lower crystal quality and imperfect exfoliation, which undermines wafer reusability and device performance. Here we report the MBE growth of amorphous boron nitride (a-BN) on InP wafers at low temperature that enabled improved quality of remote epitaxial and nanopatterned epitaxial films and their perfect exfoliation. We show fully covered a-BN on InP substrates despite their low decomposition temperatures. The surface of a-BN coated InP substrate remains smooth with a RMS roughness of around 3Å. We also demonstrate 100% coverage of single-crystal InP thin films grown on a-BN, with the film's quality significantly improved compared to the case of transferred 2D materials. In addition, the growth and exfoliation were successfully repeated multiple times, proving the feasibility for InP wafer recycling. Through this low temperature MBE growth approach with remote epitaxy and nanopatterned epitaxy, we successfully demonstrate large-scale flexible thin film exfoliation and recycling of InP substrates, which will lead to new opportunities in InP thin film-based photonics and novel heterostructures with significantly reduced cost.

Lu, Kuangye↗
DOE OSTI2024

The linear thermal expansion of 11 polymers from approximately -100 to +100°C

The linear coefficient of thermal expansion has been measured for 11 polymers from approximately -100 to +100°C. The polymers tested were poly(tetrafluoroethylene) (PTFE), poly(chlorotrifluoroethylene) (PCTFE), three polyethylenes; high density (HDPE), ultra-high molecular weight (UHMWPE) and cross-linked (XPE). The commercial fluoropolymers Kel-F 800 (also known as FK-800®) and THV 500®were tested together with samples of poly(ether ether ketone) (PEEK), poly(methyl methyl methacrylate) (PMMA), polycarbonate (PC) and poly(vinylidene fluoride) (PVDF). Polynomial fits were made to the data over appropriate ranges allowing the expansivity (α) to be estimated.

36 MATERIALS SCIENCE↗