Search NASA⌕ Search

DOE OSTI · 1682654

Materials Data on Ca6MnAl11 by Materials Project

Abstract

Ca6MnAl11 is Hexagonal Laves-derived structured and crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are twenty-four inequivalent Ca sites. In the first Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Mn and nine Al atoms. All Ca–Mn bond lengths are 3.34 Å. There are three shorter (3.21 Å) and six longer (3.32 Å) Ca–Al bond lengths. In the second Ca site, Ca is bonded in a 12-coordinate geometry to four Ca, three equivalent Mn, and nine Al atoms. There are one shorter (3.36 Å) and three longer (3.48 Å) Ca–Ca bond lengths. All Ca–Mn bond lengths are 3.35 Å. There are three shorter (3.22 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the third Ca site, Ca is bonded in a 12-coordinate geometry to four Ca, three equivalent Mn, and nine Al atoms. There are one shorter (3.36 Å) and three longer (3.48 Å) Ca–Ca bond lengths. All Ca–Mn bond lengths are 3.35 Å. There are three shorter (3.22 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the fourth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Mn and nine Al atoms. All Ca–Mn bond lengths are 3.34 Å. There are three shorter (3.21 Å) and six longer (3.32 Å) Ca–Al bond lengths. In the fifth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. All Ca–Ca bond lengths are 3.50 Å. There are a spread of Ca–Al bond distances ranging from 3.27–3.35 Å. In the sixth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. All Ca–Ca bond lengths are 3.50 Å. There are a spread of Ca–Al bond distances ranging from 3.27–3.35 Å. In the seventh Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are one shorter (3.38 Å) and three longer (3.48 Å) Ca–Ca bond lengths. There are a spread of Ca–Al bond distances ranging from 3.32–3.36 Å. In the eighth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are one shorter (3.34 Å) and three longer (3.50 Å) Ca–Ca bond lengths. There are nine shorter (3.29 Å) and three longer (3.37 Å) Ca–Al bond lengths. In the ninth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are one shorter (3.33 Å) and three longer (3.50 Å) Ca–Ca bond lengths. There are nine shorter (3.29 Å) and three longer (3.37 Å) Ca–Al bond lengths. In the tenth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. All Ca–Ca bond lengths are 3.48 Å. There are nine shorter (3.32 Å) and three longer (3.36 Å) Ca–Al bond lengths. In the eleventh Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. All Ca–Ca bond lengths are 3.48 Å. There are nine shorter (3.32 Å) and three longer (3.36 Å) Ca–Al bond lengths. In the twelfth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. All Ca–Ca bond lengths are 3.48 Å. There are nine shorter (3.32 Å) and three longer (3.36 Å) Ca–Al bond lengths. In the thirteenth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca and twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.27–3.35 Å. In the fourteenth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. The Ca–Ca bond length is 3.37 Å. There are a spread of Ca–Al bond distances ranging from 3.26–3.33 Å. In the fifteenth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. The Ca–Ca bond length is 3.37 Å. There are a spread of Ca–Al bond distances ranging from 3.26–3.33 Å. In the sixteenth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca and twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.27–3.36 Å. In the seventeenth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca and twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.27–3.35 Å. In the eighteenth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca and twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.27–3.36 Å. In the nineteenth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Mn and nine Al atoms. All Ca–Mn bond lengths are 3.35 Å. There are three shorter (3.26 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the twentieth Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca, three equivalent Mn, and nine Al atoms. All Ca–Mn bond lengths are 3.34 Å. There are three shorter (3.22 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the twenty-first Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca, three equivalent Mn, and nine Al atoms. All Ca–Mn bond lengths are 3.34 Å. There are three shorter (3.22 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the twenty-second Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Mn and nine Al atoms. All Ca–Mn bond lengths are 3.35 Å. There are three shorter (3.25 Å) and six longer (3.29 Å) Ca–Al bond lengths. In the twenty-third Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are a spread of Ca–Al bond distances ranging from 3.31–3.35 Å. In the twenty-fourth Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are nine shorter (3.31 Å) and three longer (3.35 Å) Ca–Al bond lengths. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded to six Ca and six Al atoms to form MnCa6Al6 cuboctahedra that share corners with three equivalent MnCa6Al6 cuboctahedra, corners with twelve AlCa6MnAl5 cuboctahedra, edges with six equivalent MnCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. There are three shorter (2.75 Å) and three longer (2.79 Å) Mn–Al bond lengths. In the second Mn site, Mn is bonded to six Ca and six Al atoms to form MnCa6Al6 cuboctahedra that share corners with fifteen AlCa6Al6 cuboctahedra, edges with six equivalent MnCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. There are three shorter (2.72 Å) and three longer (2.75 Å) Mn–Al bond lengths. In the third Mn site, Mn is bonded to six Ca and six Al atoms to form MnCa6Al6 cuboctahedra that share corners with fifteen AlCa6Al6 cuboctahedra, edges with six equivalent MnCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. There are three shorter (2.72 Å) and three longer (2.75 Å) Mn–Al bond lengths. In the fourth Mn site, Mn is bonded to six Ca and six Al atoms to form MnCa6Al6 cuboctahedra that share corners with three equivalent MnCa6Al6 cuboctahedra, corners with twelve AlCa6Mn2Al4 cuboctahedra, edges with six equivalent MnCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. There are three shorter (2.75 Å) and three longer (2.78 Å) Mn–Al bond lengths. There are twenty inequivalent Al sites. In the first Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6Mn2Al4 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.79–2.86 Å. In the second Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6Al6 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.79–2.86 Å. In the third Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.79–2.87 Å. In the fourth Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.79–2.87 Å. In the fifth Al site, Al is bonded to six Ca and six Al atoms to form a mixture of corner, edge, and face-sharing AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.77–2.93 Å. In the sixth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with eighteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, and faces with eighteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.77–2.93 Å. In the seventh Al site, Al is bonded to six Ca, two Mn, and four equivalent Al atoms to form AlCa6Mn2Al4 cuboctahedra that share corners with four MnCa6Al6 cuboctahedra, corners with fourteen AlCa6MnAl5 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, faces with six MnCa6Al6 cuboctahedra, and faces with twelve AlCa6MnAl5 cuboctahedra. There are two shorter (2.85 Å) and two longer (2.86 Å) Al–Al bond lengths. In the eighth Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.81–2.90 Å. In the ninth Al site, Al is bonded to six Ca, one Mn, and five Al atoms to form AlCa6MnAl5 cuboctahedra that share corners with two equivalent MnCa6Al6 cuboctahedra, corners with sixteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, faces with three equivalent MnCa6Al6 cuboctahedra, and faces with fifteen AlCa6Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.80–2.91 Å. In the tenth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with eighteen AlCa6Al6 cuboctahedra, edges with six AlCa6MnAl5 cuboctahedra, and faces with eighteen AlCa6Al6 cuboctahedra. There are four shorter (2.85 Å) and two longer (2.87 Å) Al–Al bond lengths. In the eleventh Al site, Al is bonded to six Ca and six Al atoms to form a mixture of corner, edge, and face-sharing AlCa6Al6 cuboctahedra. There are four shorter (2.85 Å) and two longer (2.86 Å) Al–Al bond lengths. In the twelfth Al site, Al is bonded to six Ca and six Al atoms to form a mixture of corner, edge, and face-sharing AlCa6Al6 cuboctahedra. There are four shorter (2.85 Å) and two longer (2.86 Å) Al–Al bond lengths. In the thirteenth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with three equivalent MnCa6Al6 cuboctahedra, corners with twelve AlCa6Al6 cuboctahedra, edges with six equivalent AlCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. In the fourteenth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with three equivalent MnCa6Al6 cuboctahedra, corners with twelve AlCa6Al6 cuboctahedra, edges with six equivalent AlCa6Al6 cuboctahedra, and faces with nineteen AlCa6Al6 cuboctahedra. In the fifteenth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with fifteen AlCa6MnAl5 cuboctahedra, edges with six equivalent AlCa6Al6 cuboctahedra, a faceface with one MnCa6Al6 cuboctahedra, and faces with eighteen AlCa6MnAl5 cuboctahedra. In the sixteenth Al site, Al is bonded to six Ca an

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2020-04-29. Materials Data on Ca6MnAl11 by Materials Project. https://doi.org/10.17188/1682654

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↗