Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “KRbMg6O7”

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.

2 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on KRbMg6O7 by Materials Project

RbKMg6O7 crystallizes in the tetragonal P4mm space group. The structure is two-dimensional and consists of one RbKMg6O7 sheet oriented in the (0, 0, 1) direction. Rb1+ is bonded in a 5-coordinate geometry to four equivalent O2- atoms. All Rb–O bond lengths are 2.67 Å. K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are four shorter (2.51 Å) and one longer (3.17 Å) K–O bond lengths. There are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Mg–O bond lengths are 2.08 Å. In the second Mg2+ site, Mg2+ is bonded in a rectangular see-saw-like geometry to four equivalent O2- atoms. All Mg–O bond lengths are 2.08 Å. In the third Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Mg–O bond distances ranging from 2.05–2.07 Å. In the fourth Mg2+ site, Mg2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are two shorter (2.07 Å) and two longer (2.08 Å) Mg–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to four equivalent Mg2+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one K1+ and four equivalent Mg2+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to four equivalent Mg2+ atoms. In the fourth O2- site, O2- is bonded to two equivalent K1+ and three Mg2+ atoms to form a mixture of corner and edge-sharing OK2Mg3 trigonal bipyramids. In the fifth O2- site, O2- is bonded to two equivalent Rb1+ and three Mg2+ atoms to form distorted ORb2Mg3 trigonal bipyramids that share corners with five OK2Mg3 trigonal bipyramids and edges with four equivalent ORb2Mg3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KRbMg6O7 by Materials Project

RbKMg6O7 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Rb1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are four shorter (2.60 Å) and one longer (3.28 Å) Rb–O bond lengths. K1+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms. All K–O bond lengths are 2.45 Å. There are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra and edges with eight MgO5 square pyramids. The corner-sharing octahedral tilt angles are 7°. There are a spread of Mg–O bond distances ranging from 2.00–2.39 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 square pyramids that share corners with four equivalent MgO5 square pyramids, edges with four equivalent MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. There are one shorter (2.11 Å) and four longer (2.15 Å) Mg–O bond lengths. In the third Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Mg–O bond distances ranging from 1.87–2.59 Å. In the fourth Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 square pyramids that share corners with four equivalent MgO5 square pyramids, edges with two equivalent MgO6 octahedra, and edges with six MgO5 square pyramids. There are one shorter (2.07 Å) and four longer (2.15 Å) Mg–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Mg2+ atoms to form distorted OMg5 square pyramids that share corners with five OMg5 square pyramids and edges with four equivalent OMg6 octahedra. In the second O2- site, O2- is bonded to five Mg2+ atoms to form distorted OMg5 square pyramids that share corners with five OMg5 square pyramids, edges with four equivalent OMg6 octahedra, and edges with four equivalent ORbMg5 square pyramids. In the third O2- site, O2- is bonded to one Rb1+ and five Mg2+ atoms to form distorted ORbMg5 square pyramids that share corners with four equivalent ORbMg5 square pyramids, edges with four equivalent OMg6 octahedra, and edges with four equivalent OMg5 square pyramids. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Rb1+, two equivalent K1+, and one Mg2+ atom. In the fifth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with four equivalent OMg6 octahedra, and edges with six OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 4–7°.

36 MATERIALS SCIENCE↗