Search NASA⌕ Search

DOE OSTI · 1689021

Materials Data on Mg149Pb by Materials Project

Abstract

Mg149Pb is alpha Samarium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are twenty-seven inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted single-bond geometry to seven Mg and one Pb atom. There are a spread of Mg–Mg bond distances ranging from 3.16–3.18 Å. The Mg–Pb bond length is 3.23 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with sixteen MgMg12 cuboctahedra, an edgeedge with one PbMg12 cuboctahedra, edges with thirteen MgMg12 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are eight shorter (3.18 Å) and two longer (3.20 Å) Mg–Mg bond lengths. In the third Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with sixteen MgMg12 cuboctahedra, an edgeedge with one PbMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are six shorter (3.18 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one PbMg12 cuboctahedra, corners with sixteen MgMg12 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.16–3.18 Å. In the sixth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are six shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the seventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are five shorter (3.18 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the eighth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. In the ninth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with sixteen MgMg12 cuboctahedra, an edgeedge with one PbMg12 cuboctahedra, edges with fifteen MgMg12 cuboctahedra, and faces with seventeen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.19 Å. In the tenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the eleventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. In the twelfth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with sixteen MgMg12 cuboctahedra, edges with fifteen MgMg12 cuboctahedra, a faceface with one PbMg12 cuboctahedra, and faces with fifteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.19 Å. In the thirteenth Mg site, Mg is bonded in a distorted single-bond geometry to seven Mg and one Pb atom. There are two shorter (3.15 Å) and one longer (3.17 Å) Mg–Mg bond lengths. The Mg–Pb bond length is 3.23 Å. In the fourteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and six longer (3.19 Å) Mg–Mg bond lengths. In the fifteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and six longer (3.19 Å) Mg–Mg bond lengths. In the sixteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are five shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the seventeenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and three longer (3.19 Å) Mg–Mg bond lengths. In the eighteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the nineteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with twelve MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one PbMg12 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are three shorter (3.17 Å) and six longer (3.19 Å) Mg–Mg bond lengths. In the twentieth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one PbMg12 cuboctahedra, corners with fifteen MgMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with seventeen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.19 Å. In the twenty-first Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the twenty-second Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. There are one shorter (3.18 Å) and five longer (3.19 Å) Mg–Mg bond lengths. In the twenty-third Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. In the twenty-fourth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. In the twenty-fifth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the twenty-sixth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. In the twenty-seventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of edge, face, and corner-sharing MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. Pb is bonded to twelve Mg atoms to form PbMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with eight MgMg12 cuboctahedra.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2019-01-11. Materials Data on Mg149Pb by Materials Project. https://doi.org/10.17188/1689021

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related reports

Cyclic moisture reactivation of calcium sorbents for long duration thermochemical energy storage

The transition to a flexible and reliable energy infrastructure, using electro-thermal energy generation technologies such as geothermal, concentrated solar power, and nuclear, usually demands simultaneous advancement of thermal energy storage (TES) to support on-demand electricity generation and industrial applications while mitigating the inherent intermittency of renewable energy sources and power outages from direct energy generation. Among TES technologies, thermochemical energy storage (TCES) based on calcium looping emerges as a compelling high-power energy storage candidate due to its high reaction enthalpy, compatibility with elevated operating temperatures, and abundance of low-cost materials. However, the long-term durability of calcium-based sorbents for TCES is hindered by surface sintering and particle aggregation, leading to performance degradation over repeated thermal cycles. This study explores a moisture hydration-based strategy to regenerate a degraded calcium sorbent and mitigate performance degradation for long duration TCES. The addition of moisture transforms calcium oxide into calcium hydroxide and produces intercalation water layers, associated with a regenerated surface area and reduced calcium oxide crystallite size. Both these effects are beneficial in restoring the sorbents' reactivity for carbonization. Additionally, an optimized hydration-assisted reactivation protocol balances the recovered energy storage capacity with heating penalty required for moisture removal from hydrated samples, resulting in an enhanced energy storage capacity up to 176% compared to benchmark sorbents that undergo cycling without reactivation after 60 cycles. In conclusion, these results highlight the potential of hydration-assisted reactivation to enhance the long-term performance of TCES, providing an effective pathway to advancing electro-thermal storage technologies.

36 MATERIALS SCIENCE↗