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At least 1,783 records · Page 99
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DOE OSTI2020

Materials Data on AgAu(IO3)4 by Materials Project

AuAg(O3I)4 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Au3+ is bonded in a square co-planar geometry to four O2- atoms. There are one shorter (2.02 Å) and three longer (2.03 Å) Au–O bond lengths. Ag1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ag–O bond distances ranging from 2.41–2.87 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Au3+, one Ag1+, and one I5+ atom. The O–I bond length is 1.93 Å. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Au3+, one Ag1+, and one I5+ atom. The O–I bond length is 1.92 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Au3+ and one I5+ atom. The O–I bond length is 1.93 Å. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Au3+ and one I5+ atom. The O–I bond length is 1.93 Å. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Ag1+ and one I5+ atom. The O–I bond length is 1.89 Å. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Ag1+ and one I5+ atom. The O–I bond length is 1.86 Å. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Ag1+ and two I5+ atoms. There are one shorter (1.84 Å) and one longer (2.61 Å) O–I bond lengths. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to two I5+ atoms. There are one shorter (1.82 Å) and one longer (2.56 Å) O–I bond lengths. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to two I5+ atoms. There are one shorter (1.83 Å) and one longer (2.55 Å) O–I bond lengths. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two I5+ atoms. There are one shorter (1.84 Å) and one longer (2.51 Å) O–I bond lengths. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one I5+ atom. The O–I bond length is 1.80 Å. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Ag1+ and one I5+ atom. The O–I bond length is 1.81 Å. There are four inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 5-coordinate geometry to five O2- atoms. In the second I5+ site, I5+ is bonded in a 5-coordinate geometry to five O2- atoms. In the third I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the fourth I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaNb14O36 by Materials Project

NaNb14O36 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Na is bonded in a square co-planar geometry to four equivalent O atoms. All Na–O bond lengths are 2.55 Å. There are five inequivalent Nb sites. In the first Nb site, Nb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Nb–O bond distances ranging from 1.80–2.40 Å. In the second Nb site, Nb is bonded to six O atoms to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–31°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the third Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 7–16°. There are a spread of Nb–O bond distances ranging from 1.92–2.16 Å. In the fourth Nb site, Nb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Nb–O bond distances ranging from 1.82–2.37 Å. In the fifth Nb site, Nb is bonded to six O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–13°. There are four shorter (1.96 Å) and two longer (2.08 Å) Nb–O bond lengths. There are eleven inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the second O site, O is bonded in a linear geometry to two Nb atoms. In the third O site, O is bonded in a linear geometry to two Nb atoms. In the fourth O site, O is bonded in a linear geometry to two Nb atoms. In the fifth O site, O is bonded in a linear geometry to two Nb atoms. In the sixth O site, O is bonded in a 3-coordinate geometry to three Nb atoms. In the seventh O site, O is bonded in a 3-coordinate geometry to three equivalent Nb atoms. In the eighth O site, O is bonded in a linear geometry to two equivalent Nb atoms. In the ninth O site, O is bonded to two equivalent Na and two equivalent Nb atoms to form ONa2Nb2 tetrahedra that share corners with four equivalent ONa2Nb2 tetrahedra, an edgeedge with one ONa2Nb2 tetrahedra, and an edgeedge with one ONb4 trigonal pyramid. In the tenth O site, O is bonded to four Nb atoms to form distorted ONb4 trigonal pyramids that share corners with two equivalent ONb4 trigonal pyramids and an edgeedge with one ONa2Nb2 tetrahedra. In the eleventh O site, O is bonded in a linear geometry to two Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaB2Pt2C by Materials Project

LaPt2B2C crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. La2+ is bonded in a distorted square co-planar geometry to four equivalent C4- atoms. All La–C bond lengths are 2.76 Å. Pt2- is bonded to four equivalent B3+ atoms to form a mixture of distorted corner and edge-sharing PtB4 tetrahedra. All Pt–B bond lengths are 2.29 Å. B3+ is bonded in a distorted single-bond geometry to four equivalent Pt2- and one C4- atom. The B–C bond length is 1.49 Å. C4- is bonded in a distorted linear geometry to four equivalent La2+ and two equivalent B3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuF2 by Materials Project

CuF2 is zeta iron carbide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Cu2+ is bonded to six equivalent F1- atoms to form a mixture of corner and edge-sharing CuF6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of Cu–F bond distances ranging from 1.95–2.27 Å. F1- is bonded in a distorted trigonal planar geometry to three equivalent Cu2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SnO2 by Materials Project

SnO2 is Hydrophilite-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Sn4+ is bonded to six equivalent O2- atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are a spread of Sn–O bond distances ranging from 2.07–2.14 Å. O2- is bonded in a distorted trigonal planar geometry to three equivalent Sn4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PbO2 by Materials Project

PbO2 is Hydrophilite-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Pb4+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing PbO6 octahedra. The corner-sharing octahedra tilt angles range from 54–55°. There are a spread of Pb–O bond distances ranging from 2.18–2.27 Å. O2- is bonded in a distorted trigonal planar geometry to three equivalent Pb4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnF2 by Materials Project

MnF2 is Hydrophilite-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Mn2+ is bonded to six equivalent F1- atoms to form a mixture of edge and corner-sharing MnF6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Mn–F bond distances ranging from 2.12–2.20 Å. F1- is bonded in a distorted trigonal planar geometry to three equivalent Mn2+ atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1992

Continuation of tailored composite structures of ordered staple thermoplastic material

The search for the cost effective composite structure has motivated the investigation of several approaches to develop composite structure from innovative material forms. Among the promising approaches is the conversion of a planar sheet to components of complex curvature through sheet forming or stretch forming. In both cases, the potential for material stretch in the fiber direction appears to offer a clear advantage in formability over continuous fiber systems. A framework was established which allows the simulation of the anisotropic mechanisms of deformation of long discontinuous fiber laminates wherein the matrix phase is a viscous fluid. Predictions for the effective viscosities of a hyper-anisotropic medium consisting of collimated, discontinuous fibers suspended in viscous matrix were extended to capture the characteristics of typical polymers including non-Newtonian behavior and temperature dependence. In addition, the influence of fiber misorientation was also modeled by compliance averaging to determine ensemble properties for a given orientation distribution. A design tool is presented for predicting the effect of material heterogeneity on the performance of curved composite beams such as those used in aircraft fuselage structures. Material heterogeneity can be induced during manufacturing processes such as sheet forming and stretch forming of thermoplastic composites. This heterogeneity can be introduced in the form of fiber realignment and spreading during the manufacturing process causing radial and tangential gradients in material properties. Two analysis procedures are used to solve the beam problems. The first method uses separate two-dimensional elasticity solutions for the stresses in the flange and web sections of the beam. The separate solutions are coupled by requiring that forces and displacements match section boundaries. The second method uses an approximate Rayleigh-Ritz technique to find the solutions for more complex beams. Analyses are performed for curved beams of various cross-sections loaded in pure bending and with a uniform distributed load. Preliminary results show that the geometry of the beam dictates the effect of heterogeneity on performance. The role of heterogeneity is larger in beams with a small average radius-to-depth ration, R/t, where R is the average radius of the beam and t is the difference between the inside and outside radii. Results of the anlysis are in the form of stresses and displacements and are compared to both mechanics of materials and numerical solutions obtained using finite element analysis.

Santare, Michael H.↗
NASA NTRS1991

Long discontinuous fiber composite structure: Forming and structural mechanics

Cost effective composite structure has motivated the investigation of several new approaches to develop composite structure from innovative material forms. Among the promising new approaches is the conversion of planar sheet to components of complex curvature through sheet forming or stretch forming. In both cases, the potential for material stretch in the fiber direction appears to offer a clear advantage in formability over continuous fiber systems. In the present study, the authors have established a framework which allows the simulation of the anisotropic mechanisms of deformation of long discontinuous fiber laminates wherein the matrix phase is a viscous fluid. The initial study focuses upon the establishment of micromechanics models for prediction of the effective anisotropic viscosities of the oriented fiber assembly in a viscous matrix. Next, the developed constitutive relation is employed through an analogy with incompressible elasticity to exercise the finite element technique for determination of local fiber orientation and laminate thickness after forming. Results are presented for the stretch bending of a curved beam from an arbitrary composite laminate and the bulging of a clamped sheet. Structural analyses are conducted to determine the effect of microstructure on the performance of curved beams manufactured from long discontinuous fiber composites. For the purposes of this study, several curved beams with ideal and non-ideal microstructures are compared for response under pure bending. Material parameters are determined from a separate microstructural analysis.

Pipes, R. B.↗
DOE OSTI2020

Materials Data on CsK2Pt by Materials Project

CsK2Pt crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Cs is bonded in a distorted square co-planar geometry to four Pt atoms. All Cs–Pt bond lengths are 3.99 Å. K is bonded in a bent 120 degrees geometry to two equivalent Pt atoms. Both K–Pt bond lengths are 3.31 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a distorted body-centered cubic geometry to four equivalent Cs and four equivalent K atoms. All Pt–K bond lengths are 3.31 Å. In the second Pt site, Pt is bonded in a 8-coordinate geometry to four equivalent Cs and four equivalent K atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNb13O33 by Materials Project

LiNb13O33 is Potassium Silver Cyanide-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Li1+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Li–O bond lengths are 2.54 Å. There are seven inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 1–18°. There are a spread of Nb–O bond distances ranging from 1.87–2.23 Å. In the second Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.81–2.41 Å. In the third Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.79–2.42 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 2–33°. There are a spread of Nb–O bond distances ranging from 1.85–2.29 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 3–34°. There are a spread of Nb–O bond distances ranging from 1.84–2.29 Å. In the sixth Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.80–2.36 Å. In the seventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There is two shorter (1.93 Å) and four longer (2.04 Å) Nb–O bond length. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the third O2- site, O2- is bonded to two equivalent Li1+ and two Nb5+ atoms to form a mixture of edge and corner-sharing OLi2Nb2 tetrahedra. In the fourth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to four Nb5+ atoms. In the ninth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuAu by Materials Project

AuCu crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Au1- is bonded in a 12-coordinate geometry to six equivalent Cu1+ atoms. All Au–Cu bond lengths are 2.70 Å. Cu1+ is bonded in a distorted hexagonal planar geometry to six equivalent Au1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TiO2 by Materials Project

TiO2 is zeta iron carbide-like structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Ti4+ is bonded to six equivalent O2- atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Ti–O bond distances ranging from 1.88–2.13 Å. O2- is bonded in a distorted trigonal planar geometry to three equivalent Ti4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ScS2 by Materials Project

ScS2 is Rutile structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Sc3+ is bonded to six equivalent S+1.50- atoms to form a mixture of edge and corner-sharing ScS6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are two shorter (2.54 Å) and four longer (2.57 Å) Sc–S bond lengths. S+1.50- is bonded in a distorted trigonal planar geometry to three equivalent Sc3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on InS2 by Materials Project

InS2 is Rutile structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. In3+ is bonded to six equivalent S+1.50- atoms to form a mixture of edge and corner-sharing InS6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are four shorter (2.60 Å) and two longer (2.67 Å) In–S bond lengths. S+1.50- is bonded in a distorted trigonal planar geometry to three equivalent In3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr2Mg by Materials Project

Sr2Mg1 crystallizes in the orthorhombic Cmcm space group. The structure is two-dimensional and consists of two Sr2Mg1 sheets oriented in the (0, 1, 0) direction. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 12-coordinate geometry to four equivalent Mg atoms. There are two shorter (3.55 Å) and two longer (3.68 Å) Sr–Mg bond lengths. In the second Sr site, Sr is bonded in a 12-coordinate geometry to two equivalent Mg atoms. Both Sr–Mg bond lengths are 3.69 Å. Mg is bonded in a distorted hexagonal planar geometry to six Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiLa5Ti8O24 by Materials Project

LiLa5Ti8O24 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Li1+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.95–2.04 Å. There are five inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.40–2.86 Å. In the second La3+ site, La3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of La–O bond distances ranging from 2.47–3.06 Å. In the third La3+ site, La3+ is bonded in a 12-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.57–2.82 Å. In the fourth La3+ site, La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share faces with two equivalent LaO12 cuboctahedra and faces with eight TiO6 octahedra. There are a spread of La–O bond distances ranging from 2.51–3.02 Å. In the fifth La3+ site, La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share faces with two equivalent LaO12 cuboctahedra and faces with eight TiO6 octahedra. There are a spread of La–O bond distances ranging from 2.47–2.98 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 6–17°. There are a spread of Ti–O bond distances ranging from 1.91–2.03 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 9–22°. There are a spread of Ti–O bond distances ranging from 1.85–2.13 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 9–23°. There are a spread of Ti–O bond distances ranging from 1.86–2.10 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with two LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 6–20°. There are a spread of Ti–O bond distances ranging from 1.91–2.05 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Ti4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and two equivalent Ti4+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and two Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and two Ti4+ atoms. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, two La3+, and two Ti4+ atoms. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, two La3+, and two equivalent Ti4+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Ti4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, two La3+, and two equivalent Ti4+ atoms. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and two equivalent Ti4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and two Ti4+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two equivalent Ti4+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and two equivalent Ti4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnPb3 by Materials Project

ZnPb3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Zn is bonded in a distorted square co-planar geometry to twelve Pb atoms. There are four shorter (3.35 Å) and eight longer (3.47 Å) Zn–Pb bond lengths. There are two inequivalent Pb sites. In the first Pb site, Pb is bonded to four equivalent Zn and eight Pb atoms to form a mixture of distorted corner, edge, and face-sharing PbZn4Pb8 cuboctahedra. There are four shorter (3.35 Å) and four longer (3.47 Å) Pb–Pb bond lengths. In the second Pb site, Pb is bonded to four equivalent Zn and eight equivalent Pb atoms to form a mixture of distorted corner, edge, and face-sharing PbZn4Pb8 cuboctahedra.

36 MATERIALS SCIENCE↗