Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “La-Pb”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Structural transition and possible pressure-induced superconductivity in a suboxide La 5 Pb 3 O

Here, in this study, we report a structural phase transition and its interplay with superconductivity in the suboxide La 5⁢ Pb 3 ⁢O. Upon cooling through 𝑇 𝑡 = 225K, La 5⁢ Pb 3⁢ O transforms from a high-temperature 𝐼⁢4/mcm to a low-temperature 𝑃⁢4/ncc structure in which La-Pb dimerization along the 𝑐 axis occurs. This transition is accompanied by anomalies in the temperature dependence of electrical resistivity and specific heat. High-pressure electrical transport measurements reveal that hydrostatic pressure suppresses the structural transition and possibly induces superconductivity with a maximum superconducting temperature of 10 K. Density functional theory calculations show minimal changes in the electronic density of states and no gap opening at 𝐸 𝐹 across 𝑇 𝑡 , suggesting that the transition is driven by bonding effects rather than Fermi surface instability. These findings establish La 5⁢ Pb 3 ⁢O as a promising platform for exploring the interplay between weak structural transitions and superconductivity.

Yan, Jiaqiang [Oak Ridge National Laboratory (ORNL↗
DOE OSTI2020

Materials Data on LaPb3 by Materials Project

LaPb3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. La is bonded to twelve equivalent Pb atoms to form a mixture of corner and face-sharing LaPb12 cuboctahedra. All La–Pb bond lengths are 3.51 Å. Pb is bonded in a distorted square co-planar geometry to four equivalent La atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La5Pb4 by Materials Project

La5Pb4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent La sites. In the first La site, La is bonded to six Pb atoms to form a mixture of distorted corner, edge, and face-sharing LaPb6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of La–Pb bond distances ranging from 3.26–3.47 Å. In the second La site, La is bonded in a 7-coordinate geometry to seven Pb atoms. There are a spread of La–Pb bond distances ranging from 3.36–4.10 Å. In the third La site, La is bonded to six Pb atoms to form a mixture of corner and face-sharing LaPb6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of La–Pb bond distances ranging from 3.33–3.50 Å. There are three inequivalent Pb sites. In the first Pb site, Pb is bonded in a 9-coordinate geometry to eight La and one Pb atom. The Pb–Pb bond length is 3.21 Å. In the second Pb site, Pb is bonded in a 9-coordinate geometry to eight La and one Pb atom. In the third Pb site, Pb is bonded in a 7-coordinate geometry to eight La atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La4Pb3 by Materials Project

La4Pb3 crystallizes in the cubic I-43d space group. The structure is three-dimensional. La is bonded to six equivalent Pb atoms to form a mixture of distorted corner, edge, and face-sharing LaPb6 octahedra. The corner-sharing octahedra tilt angles range from 19–49°. There are three shorter (3.31 Å) and three longer (3.57 Å) La–Pb bond lengths. Pb is bonded to eight equivalent La atoms to form a mixture of distorted corner, edge, and face-sharing PbLa8 hexagonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La3Pb by Materials Project

La3Pb is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. La is bonded in a distorted square co-planar geometry to four equivalent Pb atoms. All La–Pb bond lengths are 3.60 Å. Pb is bonded to twelve equivalent La atoms to form a mixture of face and corner-sharing PbLa12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La5Pb3 by Materials Project

La5Pb3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded in a 6-coordinate geometry to six equivalent Pb atoms. All La–Pb bond lengths are 3.46 Å. In the second La site, La is bonded in a 5-coordinate geometry to five equivalent Pb atoms. There are a spread of La–Pb bond distances ranging from 3.30–3.76 Å. Pb is bonded in a 9-coordinate geometry to nine La atoms.

36 MATERIALS SCIENCE↗