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At least 505 records · Page 28
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on KMg3(SiO3)4 by Materials Project

KMg3(SiO3)4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. K is bonded to twelve O atoms to form KO12 cuboctahedra that share edges with six equivalent KO12 cuboctahedra and edges with twelve SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 3.05–3.16 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.17 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six equivalent MgO6 octahedra. There are two shorter (2.06 Å) and four longer (2.12 Å) Mg–O bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with three equivalent SiO4 tetrahedra, and edges with three equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 55–58°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with three equivalent SiO4 tetrahedra, and edges with three equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 55–58°. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two equivalent Si atoms. In the third O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two equivalent Si atoms. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent K and two equivalent Si atoms. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Mg atoms. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent K and two equivalent Si atoms. In the seventh O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the eighth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KMg3(SiO3)4 by Materials Project

KMg3(SiO3)4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. K is bonded to twelve O atoms to form KO12 cuboctahedra that share edges with six equivalent KO12 cuboctahedra and edges with twelve SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 3.15–3.22 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.14 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.12 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with three equivalent SiO4 tetrahedra, and edges with three equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 54–59°. There is one shorter (1.61 Å) and three longer (1.66 Å) Si–O bond length. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with three equivalent SiO4 tetrahedra, and edges with three equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 56–59°. There is one shorter (1.61 Å) and three longer (1.66 Å) Si–O bond length. There are six inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent K and two Si atoms. In the third O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two Si atoms. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Mg atoms. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent K and two Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K(WO3)6 by Materials Project

K(WO3)6 crystallizes in the trigonal P-31m space group. The structure is three-dimensional. K1+ is bonded to twelve equivalent O2- atoms to form KO12 cuboctahedra that share edges with twelve equivalent WO6 octahedra. All K–O bond lengths are 3.36 Å. W+5.83+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six equivalent WO6 octahedra and edges with two equivalent KO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–30°. There are a spread of W–O bond distances ranging from 1.93–1.96 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent W+5.83+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent W+5.83+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one K1+ and two equivalent W+5.83+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Effect of rare earth size on network structure and glass forming ability in binary aluminum garnets

Rare earth aluminate glasses are potentially useful for optical, luminescence, and laser applications. As reluctant glass formers, these materials exhibit unconventional atomic structures. To better understand how their structures correlate with glass formation, we investigate two rare earth aluminum garnet melts, La 3 Al 5 O 12 (LAG) and Yb 3 Al 5 O 12 (YbAG), which represent the relative extremes of good and poor glass forming ability in rare earth aluminates. Structural models have been refined to high-energy X-ray diffraction data over 1340–2740 K. Both melts contain mixtures of AlO 4 , AlO 5 , and AlO 6 polyhedra, with larger fractions of [5] Al and [6] Al in YbAG. Extrapolation of the Al–O coordination distributions to the glass transition match closely with 27 Al nuclear magnetic resonance measurements of (La 1−z Y z ) 3 Al 5 O 12 glasses, z = 0 to 1. During cooling, the mean coordination numbers increase for La–O in LAG from 6.45(8) to 6.98(8) and for Yb–O in YbAG from 6.02(8) to 6.21(8). Linkedness among Al–O polyhedra at ∼2450 K is mostly corner-sharing, with 9% edge-sharing in LAG and 19% in YbAG. Among [4] Al units, both melts have 6% edge-sharing that convert to all corner-sharing upon cooling. Network connectivity is compared using a newly defined metric, K n , that is similar to the Q n distribution but that accounts for the edge-sharing and triply bonded oxygen present in these melts. The lower glass forming ability in YbAG as compared to LAG correlates with more edge-sharing, associated with the larger fractions of [5] Al and [6] Al, and lower connectivity among [4] Al units.

Wilke, Stephen K. [Materials Development, Inc., Ar↗
DOE OSTI2020

Materials Data on KSn2 by Materials Project

KSn2 is Hexagonal Laves structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. K is bonded in a 12-coordinate geometry to four equivalent K and twelve Sn atoms. There are a spread of K–K bond distances ranging from 3.63–4.08 Å. There are a spread of K–Sn bond distances ranging from 3.65–3.92 Å. There are three inequivalent Sn sites. In the first Sn site, Sn is bonded to six equivalent K and six Sn atoms to form a mixture of edge, corner, and face-sharing SnK6Sn6 cuboctahedra. All Sn–Sn bond lengths are 3.16 Å. In the second Sn site, Sn is bonded to six equivalent K and six Sn atoms to form a mixture of distorted edge, corner, and face-sharing SnK6Sn6 cuboctahedra. There are a spread of Sn–Sn bond distances ranging from 3.27–3.42 Å. In the third Sn site, Sn is bonded to six equivalent K and six Sn atoms to form a mixture of distorted edge, corner, and face-sharing SnK6Sn6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KIO2 by Materials Project

KO2I crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. K is bonded to six equivalent O atoms to form edge-sharing KO6 octahedra. There are four shorter (2.67 Å) and two longer (2.93 Å) K–O bond lengths. O is bonded to three equivalent K and two equivalent I atoms to form a mixture of distorted edge and corner-sharing OK3I2 square pyramids. Both O–I bond lengths are 2.23 Å. I is bonded in a distorted square co-planar geometry to four equivalent O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K7Ta(SO4)6 by Materials Project

K7Ta(SO4)6 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six equivalent O2- atoms to form KO6 octahedra that share corners with six equivalent SO4 tetrahedra and edges with six equivalent KO6 octahedra. All K–O bond lengths are 2.74 Å. In the second K1+ site, K1+ is bonded to six O2- atoms to form KO6 octahedra that share corners with two equivalent KO6 octahedra, corners with six equivalent SO4 tetrahedra, and edges with three KO6 octahedra. The corner-sharing octahedral tilt angles are 77°. There are a spread of K–O bond distances ranging from 2.72–2.98 Å. Ta5+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Ta–O bond lengths are 1.98 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one TaO6 octahedra and corners with seven KO6 octahedra. The corner-sharing octahedra tilt angles range from 28–64°. There are a spread of S–O bond distances ranging from 1.47–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one S6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ta5+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K7Nb(SO4)6 by Materials Project

K7Nb(SO4)6 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six equivalent O2- atoms to form KO6 octahedra that share corners with six equivalent SO4 tetrahedra and edges with six equivalent KO6 octahedra. All K–O bond lengths are 2.74 Å. In the second K1+ site, K1+ is bonded to six O2- atoms to form KO6 octahedra that share corners with two equivalent KO6 octahedra, corners with six equivalent SO4 tetrahedra, and edges with three KO6 octahedra. The corner-sharing octahedral tilt angles are 77°. There are a spread of K–O bond distances ranging from 2.72–2.98 Å. Nb5+ is bonded to six equivalent O2- atoms to form NbO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Nb–O bond lengths are 2.00 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one NbO6 octahedra and corners with seven KO6 octahedra. The corner-sharing octahedra tilt angles range from 29–65°. There are a spread of S–O bond distances ranging from 1.47–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb5+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K by Materials Project

K is Magnesium structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. K is bonded to twelve equivalent K atoms to form a mixture of face, edge, and corner-sharing KK12 cuboctahedra. There are six shorter (4.68 Å) and six longer (4.76 Å) K–K bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2PbO2 by Materials Project

K2PbO2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.68–2.70 Å. In the second K1+ site, K1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.69–2.92 Å. In the third K1+ site, K1+ is bonded to five O2- atoms to form edge-sharing KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.73–2.86 Å. In the fourth K1+ site, K1+ is bonded to five O2- atoms to form edge-sharing KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.70–2.90 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Pb–O bond distances ranging from 2.14–2.31 Å. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Pb–O bond distances ranging from 2.15–2.27 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four K1+ and two equivalent Pb2+ atoms to form OK4Pb2 octahedra that share corners with three equivalent OK3Pb2 trigonal bipyramids and edges with eight OK4Pb2 octahedra. In the second O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form OK5Pb octahedra that share corners with three equivalent OK5Pb octahedra, edges with four OK4Pb2 octahedra, and edges with three equivalent OK3Pb2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 10–16°. In the third O2- site, O2- is bonded to five K1+ and one Pb2+ atom to form OK5Pb octahedra that share corners with three equivalent OK5Pb octahedra, a cornercorner with one OK3Pb2 trigonal bipyramid, edges with seven OK4Pb2 octahedra, and an edgeedge with one OK3Pb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 10–16°. In the fourth O2- site, O2- is bonded to three K1+ and two equivalent Pb2+ atoms to form distorted OK3Pb2 trigonal bipyramids that share corners with four OK4Pb2 octahedra, edges with four OK5Pb octahedra, and an edgeedge with one OK3Pb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 28–78°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCd(PO3)3 by Materials Project

KCd(PO3)3 crystallizes in the hexagonal P-6c2 space group. The structure is three-dimensional. K1+ is bonded to six equivalent O2- atoms to form distorted KO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent CdO6 octahedra. All K–O bond lengths are 2.85 Å. Cd2+ is bonded to six equivalent O2- atoms to form CdO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent KO6 octahedra. All Cd–O bond lengths are 2.30 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent KO6 octahedra, corners with two equivalent CdO6 octahedra, and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–59°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Cd2+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCa(PO3)3 by Materials Project

KCa(PO3)3 crystallizes in the hexagonal P-6c2 space group. The structure is three-dimensional. K1+ is bonded to six equivalent O2- atoms to form distorted KO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent CaO6 octahedra. All K–O bond lengths are 2.85 Å. Ca2+ is bonded to six equivalent O2- atoms to form CaO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent KO6 octahedra. All Ca–O bond lengths are 2.36 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent KO6 octahedra, corners with two equivalent CaO6 octahedra, and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–58°. There is two shorter (1.50 Å) and two longer (1.62 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Ca2+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KMn(PO3)3 by Materials Project

KMn(PO3)3 crystallizes in the hexagonal P-6c2 space group. The structure is three-dimensional. K1+ is bonded to six equivalent O2- atoms to form distorted KO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent MnO6 octahedra. All K–O bond lengths are 2.81 Å. Mn2+ is bonded to six equivalent O2- atoms to form MnO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with three equivalent KO6 octahedra. All Mn–O bond lengths are 2.20 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent KO6 octahedra, corners with two equivalent MnO6 octahedra, and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–60°. There is two shorter (1.50 Å) and two longer (1.62 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Mn2+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KC by Materials Project

KC1 is Halite, Rock Salt structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. K is bonded to six equivalent C atoms to form a mixture of edge and corner-sharing KC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All K–C bond lengths are 3.09 Å. C is bonded to six equivalent K atoms to form a mixture of edge and corner-sharing CK6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KB by Materials Project

BK1 is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. K is bonded to six equivalent B atoms to form a mixture of edge and corner-sharing KB6 octahedra. The corner-sharing octahedral tilt angles are 0°. All K–B bond lengths are 3.15 Å. B is bonded to six equivalent K atoms to form a mixture of edge and corner-sharing BK6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Metal (hydr)oxide surface precipitates and their effects on potassium sorption

Surface precipitation has been shown to occur on rapid time scales in clay and metal oxide mineral systems. The formation of surface precipitates is hypothesized to present new potential sorption sites for potassium (K), where K can become incorporated into newly formed interlayer spaces (e.g., between tetrahedral–octahedral–tetrahedral stacked sheets). The objective of this study is to determine the effects of newly formed mineral surface precipitates on K sorption. Potassium adsorption experiments were conducted by utilizing Al 2 O 3 and SiO 2 sorbents in the presence of various cations (magnesium, zinc, and nickel) that helped to catalyze the formation of surface precipitates. Dissolved concentrations of elements were monitored via inductively coupled plasma optical emission spectrometry (ICP-OES). Solids were characterized via X-ray diffraction (XRD), and K surface complexation was analyzed via X-ray absorption near edge structure (XANES) spectroscopy. X-ray diffraction analysis indicated bayerite, layered double hydroxides (LDH), and silicated LDH were formed as reaction products, thus creating new surface sites for potential K adsorption. The presence of Si increased K adsorption perhaps due to its role in the formation of LDH surface precipitates. When the differences between observed and theoretical surface area normalized K sorption densities were averaged, a 31% increase in K adsorption was observed in the presence of Si. XANES analysis indicated that the binding mechanism of K to Si is different than that of K to Al, perhaps due to the presence of inner-sphere complexation of K to Al-oxide. Samples reacted for one month versus one week yielded more intense XANES post-edge peaks which indicated that the K sorption complex changes over time. Altogether, our findings provide novel insights into the mechanisms of K fixation in soil and has high implication in providing improved K fertilizer recommendation to growers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on K3CuO2 by Materials Project

K3CuO2 crystallizes in the tetragonal P4_12_12 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to four O2- atoms to form a mixture of distorted corner and edge-sharing KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.79–2.88 Å. In the second K1+ site, K1+ is bonded in a 2-coordinate geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.63–3.12 Å. In the third K1+ site, K1+ is bonded to four O2- atoms to form a mixture of distorted corner and edge-sharing KO4 tetrahedra. There are two shorter (2.79 Å) and two longer (2.94 Å) K–O bond lengths. In the fourth K1+ site, K1+ is bonded to four O2- atoms to form a mixture of corner and edge-sharing KO4 tetrahedra. There are two shorter (2.76 Å) and two longer (2.91 Å) K–O bond lengths. Cu1+ is bonded in a linear geometry to two O2- atoms. Both Cu–O bond lengths are 1.82 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 7-coordinate geometry to six K1+ and one Cu1+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to six K1+ and one Cu1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KGe by Materials Project

KGe is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. K is bonded to six equivalent Ge atoms to form a mixture of edge and corner-sharing KGe6 octahedra. The corner-sharing octahedral tilt angles are 0°. All K–Ge bond lengths are 3.41 Å. Ge is bonded to six equivalent K atoms to form a mixture of edge and corner-sharing GeK6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗