DOE OSTI2020
Na15Cr7N19 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are sixteen inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Na–N bond distances ranging from 2.52–2.94 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Na–N bond distances ranging from 2.38–2.92 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.48–2.81 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Na–N bond distances ranging from 2.36–3.02 Å. In the fifth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.40–2.61 Å. In the sixth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.38–2.88 Å. In the seventh Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.38–2.70 Å. In the eighth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.41–2.74 Å. In the ninth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.42–2.87 Å. In the tenth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Na–N bond distances ranging from 2.50–2.59 Å. In the eleventh Na1+ site, Na1+ is bonded in a distorted rectangular see-saw-like geometry to four N3- atoms. There are a spread of Na–N bond distances ranging from 2.38–2.65 Å. In the twelfth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Na–N bond distances ranging from 2.45–2.98 Å. In the thirteenth Na1+ site, Na1+ is bonded in a 3-coordinate geometry to three N3- atoms. There are a spread of Na–N bond distances ranging from 2.40–2.48 Å. In the fourteenth Na1+ site, Na1+ is bonded in a 4-coordinate geometry to six N3- atoms. There are a spread of Na–N bond distances ranging from 2.36–3.07 Å. In the fifteenth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Na–N bond distances ranging from 2.33–3.07 Å. In the sixteenth Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight N3- atoms. There are a spread of Na–N bond distances ranging from 2.55–3.12 Å. There are seven inequivalent Cr6+ sites. In the first Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There is one shorter (1.66 Å) and three longer (1.78 Å) Cr–N bond length. In the second Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.66–1.82 Å. In the third Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.67–1.82 Å. In the fourth Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.67–1.85 Å. In the fifth Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.65–1.82 Å. In the sixth Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.68–1.84 Å. In the seventh Cr6+ site, Cr6+ is bonded to four N3- atoms to form corner-sharing CrN4 tetrahedra. There are a spread of Cr–N bond distances ranging from 1.68–1.85 Å. There are nineteen inequivalent N3- sites. In the first N3- site, N3- is bonded in a 6-coordinate geometry to five Na1+ and one Cr6+ atom. In the second N3- site, N3- is bonded in a 2-coordinate geometry to four Na1+ and two Cr6+ atoms. In the third N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the fourth N3- site, N3- is bonded in a 5-coordinate geometry to three Na1+ and two Cr6+ atoms. In the fifth N3- site, N3- is bonded in a 2-coordinate geometry to three Na1+ and two Cr6+ atoms. In the sixth N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the seventh N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the eighth N3- site, N3- is bonded in a 5-coordinate geometry to three Na1+ and two Cr6+ atoms. In the ninth N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the tenth N3- site, N3- is bonded in a distorted octahedral geometry to five Na1+ and one Cr6+ atom. In the eleventh N3- site, N3- is bonded in a 2-coordinate geometry to three Na1+ and two Cr6+ atoms. In the twelfth N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the thirteenth N3- site, N3- is bonded in a 2-coordinate geometry to three Na1+ and two Cr6+ atoms. In the fourteenth N3- site, N3- is bonded in a 6-coordinate geometry to four Na1+ and two Cr6+ atoms. In the fifteenth N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the sixteenth N3- site, N3- is bonded in a 2-coordinate geometry to four Na1+ and two Cr6+ atoms. In the seventeenth N3- site, N3- is bonded in a 2-coordinate geometry to one Na1+ and two Cr6+ atoms. In the eighteenth N3- site, N3- is bonded in a 1-coordinate geometry to five Na1+ and one Cr6+ atom. In the nineteenth N3- site, N3- is bonded in a 5-coordinate geometry to four Na1+ and one Cr6+ atom.