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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Eu(AlAu)2 by Materials Project

EuAu2Al2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Eu is bonded in a 12-coordinate geometry to eight Au and eight Al atoms. There are four shorter (3.40 Å) and four longer (3.46 Å) Eu–Au bond lengths. There are four shorter (3.41 Å) and four longer (3.47 Å) Eu–Al bond lengths. There are two inequivalent Au sites. In the first Au site, Au is bonded in a 5-coordinate geometry to four equivalent Eu and five Al atoms. There are one shorter (2.55 Å) and four longer (2.63 Å) Au–Al bond lengths. In the second Au site, Au is bonded to four equivalent Eu and four equivalent Al atoms to form distorted AuEu4Al4 tetrahedra that share corners with twelve equivalent AlEu4Au4 tetrahedra, edges with two equivalent AlEu4Au4 tetrahedra, edges with four equivalent AuEu4Al4 tetrahedra, and faces with four equivalent AuEu4Al4 tetrahedra. All Au–Al bond lengths are 2.61 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 5-coordinate geometry to four equivalent Eu and five Au atoms. In the second Al site, Al is bonded to four equivalent Eu and four equivalent Au atoms to form AlEu4Au4 tetrahedra that share corners with twelve equivalent AuEu4Al4 tetrahedra, edges with two equivalent AuEu4Al4 tetrahedra, edges with four equivalent AlEu4Au4 tetrahedra, and faces with four equivalent AlEu4Au4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(ZnGe)2 by Materials Project

EuZn2Ge2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Eu is bonded in a 12-coordinate geometry to eight Zn and eight Ge atoms. There are four shorter (3.32 Å) and four longer (3.43 Å) Eu–Zn bond lengths. There are four shorter (3.31 Å) and four longer (3.43 Å) Eu–Ge bond lengths. There are two inequivalent Zn sites. In the first Zn site, Zn is bonded to four equivalent Eu and four equivalent Ge atoms to form distorted ZnEu4Ge4 tetrahedra that share corners with twelve equivalent GeEu4Zn4 tetrahedra, edges with two equivalent GeEu4Zn4 tetrahedra, edges with four equivalent ZnEu4Ge4 tetrahedra, and faces with four equivalent ZnEu4Ge4 tetrahedra. All Zn–Ge bond lengths are 2.60 Å. In the second Zn site, Zn is bonded in a 5-coordinate geometry to four equivalent Eu and five Ge atoms. There are one shorter (2.45 Å) and four longer (2.59 Å) Zn–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded to four equivalent Eu and four equivalent Zn atoms to form distorted GeEu4Zn4 tetrahedra that share corners with twelve equivalent ZnEu4Ge4 tetrahedra, edges with two equivalent ZnEu4Ge4 tetrahedra, edges with four equivalent GeEu4Zn4 tetrahedra, and faces with four equivalent GeEu4Zn4 tetrahedra. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Eu and five Zn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(PIr)2 by Materials Project

Eu(IrP)2 crystallizes in the trigonal P3_221 space group. The structure is three-dimensional. Eu is bonded in a 11-coordinate geometry to five Ir and six equivalent P atoms. There are a spread of Eu–Ir bond distances ranging from 3.18–3.35 Å. There are a spread of Eu–P bond distances ranging from 3.06–3.18 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to three equivalent Eu and four equivalent P atoms. There are two shorter (2.35 Å) and two longer (2.40 Å) Ir–P bond lengths. In the second Ir site, Ir is bonded in a 6-coordinate geometry to two equivalent Eu and four equivalent P atoms. There are two shorter (2.27 Å) and two longer (2.33 Å) Ir–P bond lengths. P is bonded to three equivalent Eu and four Ir atoms to form a mixture of distorted face, edge, and corner-sharing PEu3Ir4 pentagonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(ZnSn)2 by Materials Project

EuZn2Sn2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Eu is bonded in a 4-coordinate geometry to eight Zn and eight Sn atoms. There are a spread of Eu–Zn bond distances ranging from 3.44–3.77 Å. There are a spread of Eu–Sn bond distances ranging from 3.45–3.72 Å. There are two inequivalent Zn sites. In the first Zn site, Zn is bonded in a 9-coordinate geometry to four equivalent Eu and five Sn atoms. There are a spread of Zn–Sn bond distances ranging from 2.59–2.83 Å. In the second Zn site, Zn is bonded to four equivalent Eu and four equivalent Sn atoms to form distorted ZnEu4Sn4 tetrahedra that share corners with twelve equivalent SnEu4Zn4 tetrahedra, edges with two equivalent SnEu4Zn4 tetrahedra, edges with four equivalent ZnEu4Sn4 tetrahedra, and faces with four equivalent ZnEu4Sn4 tetrahedra. There are a spread of Zn–Sn bond distances ranging from 2.74–2.77 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 9-coordinate geometry to four equivalent Eu and five Zn atoms. In the second Sn site, Sn is bonded to four equivalent Eu and four equivalent Zn atoms to form distorted SnEu4Zn4 tetrahedra that share corners with twelve equivalent ZnEu4Sn4 tetrahedra, edges with two equivalent ZnEu4Sn4 tetrahedra, edges with four equivalent SnEu4Zn4 tetrahedra, and faces with four equivalent SnEu4Zn4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(Al2Cu)4 by Materials Project

Eu(CuAl2)4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 12-coordinate geometry to eight equivalent Cu and twelve Al atoms. All Eu–Cu bond lengths are 3.39 Å. There are four shorter (3.08 Å) and eight longer (3.22 Å) Eu–Al bond lengths. Cu is bonded in a 12-coordinate geometry to two equivalent Eu, two equivalent Cu, and eight Al atoms. Both Cu–Cu bond lengths are 2.57 Å. There are four shorter (2.57 Å) and four longer (2.70 Å) Cu–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to one Eu, four equivalent Cu, and five Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.83 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to two equivalent Eu, four equivalent Cu, and six Al atoms. Both Al–Al bond lengths are 2.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Suppression of the valence transition in solution-grown single crystals of Eu 2 Pt 6 Al 15

Here, the study of Eu intermetallic compounds has allowed the exploration of valence fluctuations and transitions in 4⁢𝑓 electron systems. Recently, a Eu 2 ⁢Pt 6 ⁢Al 15 phase synthesized by arc-melting followed by a thermal treatment was reported M. Radzieowski et al. [J. Am. Chem. Soc. 140, 8950 (2018)], which undergoes a transition upon cooling below 45 K that was interpreted as a valence transition from Eu 2+ to Eu 3+ . In this paper, we present the discovery of another polymorph of Eu 2 ⁢Pt 6 ⁢Al 15 obtained by high temperature solution growth, which presents different physical properties than the arc-melted polycrystalline sample. Despite the similarities in crystal structure and chemical composition, the Eu valence transition is almost fully suppressed in the solution-grown crystals, allowing the moments associated with the Eu 2+ state to order antiferromagnetically at around 14 K. A detailed analysis of the crystal structure using single crystal x-ray diffraction reveals that, although the solution grown crystals are built from the same constituent layers as the arc-melted samples, these layers present a different stacking. The effect of different thermal treatments is also studied. Different anneal procedures did not result in significant changes in the intrinsic properties, and only by arc-melting and quenching the crystals we were able to convert them into the previously reported polymorph.

Schmidt, Juan [Ames Laboratory, and Iowa State Uni↗
DOE OSTI2023

Valence and magnetism in EuPd 3 S 4 and (Y, La) x Eu 1-x Pd 3 S 4

151 Eu Mössbauer spectroscopy shows that yttrium substitution in mixed-valent EuPd 3 S 4 drives the initial 50:50 mix of Eu 3+ and E 2+ towards pure Eu 2+ , whereas lanthanum substitution has the opposite effect, but only for substitution levels above 50%. Here, we find that total valence electron count and chemical pressure effects cannot account for the observed behavior; however, conserving the cell volume provides a consistent description of the changes in the Eu 2+ :Eu 3+ ratio. Remarkably, lanthanum substitution also leads to a clear transition from static mixed-valent behavior at lower temperatures to dynamic mixed-valent behavior at higher temperatures, with the onset temperature monotonically increasing with Eu content and extrapolating to a value of ~ 340 K for the pure EuPd 3 S 4 compound. Magnetic order persists at least as far as x=0.875 in both series, despite the drastic reduction in the amount of moment-carrying Eu 2+ ions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on Eu(BIr)2 by Materials Project

Eu(IrB)2 is alpha Pu-derived structured and crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Eu is bonded in a 10-coordinate geometry to eight equivalent Ir and six equivalent B atoms. There are four shorter (3.08 Å) and four longer (3.34 Å) Eu–Ir bond lengths. There are two shorter (3.04 Å) and four longer (3.16 Å) Eu–B bond lengths. Ir is bonded in a 4-coordinate geometry to four equivalent Eu and four equivalent B atoms. There are two shorter (2.10 Å) and two longer (2.17 Å) Ir–B bond lengths. B is bonded in a 4-coordinate geometry to three equivalent Eu and four equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(Al2Fe)4 by Materials Project

EuFe4Al8 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 12-coordinate geometry to eight equivalent Fe and twelve Al atoms. All Eu–Fe bond lengths are 3.35 Å. There are four shorter (2.99 Å) and eight longer (3.20 Å) Eu–Al bond lengths. Fe is bonded in a 12-coordinate geometry to two equivalent Eu, two equivalent Fe, and eight Al atoms. Both Fe–Fe bond lengths are 2.51 Å. There are four shorter (2.54 Å) and four longer (2.65 Å) Fe–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded in a 10-coordinate geometry to one Eu, four equivalent Fe, and five Al atoms. There are a spread of Al–Al bond distances ranging from 2.71–2.80 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to two equivalent Eu, four equivalent Fe, and six Al atoms. Both Al–Al bond lengths are 2.79 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(GeIr)2 by Materials Project

Eu(IrGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight equivalent Ir and eight equivalent Ge atoms. All Eu–Ir bond lengths are 3.38 Å. All Eu–Ge bond lengths are 3.26 Å. Ir is bonded to four equivalent Eu and four equivalent Ge atoms to form a mixture of distorted corner, edge, and face-sharing IrEu4Ge4 tetrahedra. All Ir–Ge bond lengths are 2.48 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.66 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(InAu)3 by Materials Project

EuAu3In3 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. Eu is bonded in a 12-coordinate geometry to eight Au and four equivalent In atoms. There are a spread of Eu–Au bond distances ranging from 3.38–3.71 Å. All Eu–In bond lengths are 3.57 Å. There are two inequivalent Au sites. In the first Au site, Au is bonded in a 1-coordinate geometry to three equivalent Eu, two equivalent Au, and four In atoms. Both Au–Au bond lengths are 2.83 Å. There are one shorter (2.73 Å) and three longer (2.93 Å) Au–In bond lengths. In the second Au site, Au is bonded in a 7-coordinate geometry to two equivalent Eu and seven In atoms. There are a spread of Au–In bond distances ranging from 2.78–2.93 Å. There are two inequivalent In sites. In the first In site, In is bonded in a 7-coordinate geometry to seven Au atoms. In the second In site, In is bonded to two equivalent Eu and four Au atoms to form a mixture of distorted corner, edge, and face-sharing InEu2Au4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(AsRh)2 by Materials Project

Eu(RhAs)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight equivalent Rh and eight equivalent As atoms. All Eu–Rh bond lengths are 3.54 Å. All Eu–As bond lengths are 3.26 Å. Rh is bonded to four equivalent Eu and four equivalent As atoms to form a mixture of distorted corner, edge, and face-sharing RhEu4As4 tetrahedra. All Rh–As bond lengths are 2.48 Å. As is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Rh, and one As atom. The As–As bond length is 2.98 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(PRh)2 by Materials Project

Eu(RhP)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight equivalent Rh and eight equivalent P atoms. All Eu–Rh bond lengths are 3.21 Å. All Eu–P bond lengths are 3.09 Å. Rh is bonded in a 12-coordinate geometry to four equivalent Eu, four equivalent Rh, and four equivalent P atoms. All Rh–Rh bond lengths are 2.86 Å. All Rh–P bond lengths are 2.43 Å. P is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Rh, and one P atom. The P–P bond length is 2.30 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(GaGe2)2 by Materials Project

EuGa2Ge4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Eu is bonded in a 6-coordinate geometry to four equivalent Ga and ten Ge atoms. All Eu–Ga bond lengths are 3.41 Å. There are a spread of Eu–Ge bond distances ranging from 3.42–3.58 Å. Ga is bonded in a 6-coordinate geometry to two equivalent Eu, two equivalent Ga, and two Ge atoms. Both Ga–Ga bond lengths are 2.47 Å. There are one shorter (2.53 Å) and one longer (2.54 Å) Ga–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 1-coordinate geometry to three equivalent Eu, one Ga, and three Ge atoms. There are one shorter (2.52 Å) and two longer (2.54 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 1-coordinate geometry to two equivalent Eu, one Ga, and three Ge atoms. The Ge–Ge bond length is 2.56 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(GaGe2)2 by Materials Project

EuGa2Ge4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Eu is bonded in a 6-coordinate geometry to six equivalent Ga and eight Ge atoms. There are two shorter (3.25 Å) and four longer (3.58 Å) Eu–Ga bond lengths. There are four shorter (3.44 Å) and four longer (3.60 Å) Eu–Ge bond lengths. Ga is bonded in a 7-coordinate geometry to three equivalent Eu, one Ga, and three Ge atoms. The Ga–Ga bond length is 2.49 Å. There are one shorter (2.50 Å) and two longer (2.53 Å) Ga–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to two equivalent Eu, two equivalent Ga, and two Ge atoms. Both Ge–Ge bond lengths are 2.53 Å. In the second Ge site, Ge is bonded in a 1-coordinate geometry to two equivalent Eu, one Ga, and three Ge atoms. Both Ge–Ge bond lengths are 2.55 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(GaGe2)2 by Materials Project

EuGa2Ge4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Eu is bonded in a 10-coordinate geometry to four equivalent Ga and ten Ge atoms. All Eu–Ga bond lengths are 3.66 Å. There are a spread of Eu–Ge bond distances ranging from 3.38–3.54 Å. Ga is bonded in a 4-coordinate geometry to two equivalent Eu, one Ga, and three Ge atoms. The Ga–Ga bond length is 2.51 Å. There are two shorter (2.50 Å) and one longer (2.53 Å) Ga–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to three equivalent Eu, two equivalent Ga, and two Ge atoms. There are one shorter (2.54 Å) and one longer (2.56 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 1-coordinate geometry to two equivalent Eu, one Ga, and three Ge atoms. Both Ge–Ge bond lengths are 2.57 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(GeAu)2 by Materials Project

Eu(AuGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight equivalent Au and eight equivalent Ge atoms. All Eu–Au bond lengths are 3.46 Å. All Eu–Ge bond lengths are 3.43 Å. Au is bonded in a 4-coordinate geometry to four equivalent Eu and four equivalent Ge atoms. All Au–Ge bond lengths are 2.65 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Au, and one Ge atom. The Ge–Ge bond length is 2.49 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu(AgGe)2 by Materials Project

Eu(AgGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight equivalent Ag and eight equivalent Ge atoms. All Eu–Ag bond lengths are 3.53 Å. All Eu–Ge bond lengths are 3.35 Å. Ag is bonded in a 4-coordinate geometry to four equivalent Eu and four equivalent Ge atoms. All Ag–Ge bond lengths are 2.68 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Eu, four equivalent Ag, and one Ge atom. The Ge–Ge bond length is 2.46 Å.

36 MATERIALS SCIENCE↗