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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Sr2P6O17 by Materials Project

Sr2P6O17 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.71 Å. In the second Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–3.10 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.48–1.66 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.47–1.59 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.48–1.65 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.48–1.58 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.64 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.48–1.66 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to one Sr2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3P4O13 by Materials Project

Sr3P4O13 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.79 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.56–3.13 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–3.21 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.66 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.65 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.60 Å. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr(PO3)2 by Materials Project

Sr(PO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.76 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–2.83 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.51 Å) and two longer (1.60 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3(PO4)2 by Materials Project

Sr3(PO4)2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six equivalent O2- atoms to form distorted SrO6 cuboctahedra that share corners with six equivalent PO4 tetrahedra. All Sr–O bond lengths are 2.61 Å. In the second Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.78 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent SrO6 cuboctahedra. There is one shorter (1.55 Å) and three longer (1.56 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to four Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr(PO3)2 by Materials Project

Sr(PO3)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.03 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.05 Å. In the third Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.04 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–2.96 Å. There are eight inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.61 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.61 Å) P–O bond length. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.61 Å) P–O bond length. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.61 Å) P–O bond length. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the twentieth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr(PO3)2 by Materials Project

Sr(PO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.98 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.48–1.65 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two P5+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr2P2O7 by Materials Project

Sr2P2O7 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.88 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.58–3.03 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.53–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr4P2O by Materials Project

Sr4P2O is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to five equivalent P3- and one O2- atom. There are one shorter (3.03 Å) and four longer (3.48 Å) Sr–P bond lengths. The Sr–O bond length is 2.82 Å. In the second Sr2+ site, Sr2+ is bonded in a distorted linear geometry to four equivalent P3- and two equivalent O2- atoms. All Sr–P bond lengths are 3.25 Å. Both Sr–O bond lengths are 2.42 Å. P3- is bonded in a 9-coordinate geometry to nine Sr2+ atoms. O2- is bonded to six Sr2+ atoms to form corner-sharing OSr6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrPO4 by Materials Project

SrPO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Sr–O bond distances ranging from 2.55–3.11 Å. In the second Sr site, Sr is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Sr–O bond distances ranging from 2.56–2.77 Å. There are two inequivalent P sites. In the first P site, P is bonded in a tetrahedral geometry to four O atoms. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the second P site, P is bonded in a tetrahedral geometry to four O atoms. There is three shorter (1.54 Å) and one longer (1.55 Å) P–O bond length. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to two equivalent Sr and one P atom. In the second O site, O is bonded in a distorted single-bond geometry to three Sr and one P atom. In the third O site, O is bonded in a 1-coordinate geometry to one Sr and one P atom. In the fourth O site, O is bonded in a 1-coordinate geometry to two Sr and one P atom. In the fifth O site, O is bonded in a distorted single-bond geometry to two Sr and one P atom. In the sixth O site, O is bonded in a distorted single-bond geometry to two Sr and one P atom. In the seventh O site, O is bonded in a distorted single-bond geometry to two Sr and one P atom. In the eighth O site, O is bonded in a distorted single-bond geometry to two Sr and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5P3O14 by Materials Project

Sr5P3O14 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sr–O bond distances ranging from 2.59–2.94 Å. In the second Sr site, Sr is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.83 Å. P is bonded in a tetrahedral geometry to four O atoms. All P–O bond lengths are 1.56 Å. There are four inequivalent O sites. In the first O site, O is bonded to three equivalent Sr and one O atom to form face-sharing OSr3O tetrahedra. The O–O bond length is 1.35 Å. In the second O site, O is bonded in a distorted single-bond geometry to three Sr and one P atom. In the third O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom. In the fourth O site, O is bonded in a 4-coordinate geometry to three Sr and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr5P3O13 by Materials Project

Sr5P3O13 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. there are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sr–O bond distances ranging from 2.60–2.96 Å. In the second Sr site, Sr is bonded to seven O atoms to form distorted SrO7 pentagonal bipyramids that share corners with six equivalent SrO7 pentagonal bipyramids, corners with four equivalent PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.47–2.81 Å. P is bonded to four O atoms to form PO4 tetrahedra that share corners with four equivalent SrO7 pentagonal bipyramids and an edgeedge with one SrO7 pentagonal bipyramid. All P–O bond lengths are 1.56 Å. There are four inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to three Sr and one P atom. In the second O site, O is bonded in a trigonal planar geometry to three equivalent Sr atoms. In the third O site, O is bonded in a 4-coordinate geometry to three Sr and one P atom. In the fourth O site, O is bonded in a 1-coordinate geometry to three Sr and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr10P6O25 by Materials Project

Sr10(PO4)6O crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are six inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to six O2- atoms. There are three shorter (2.55 Å) and three longer (2.58 Å) Sr–O bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.63–2.80 Å. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.57–2.95 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.56–3.00 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.31–2.92 Å. In the sixth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with four PO4 tetrahedra and an edgeedge with one PO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.43–2.74 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SrO6 pentagonal pyramids. There is one shorter (1.55 Å) and three longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SrO6 pentagonal pyramids and an edgeedge with one SrO6 pentagonal pyramid. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to three equivalent Sr2+ atoms. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Sr2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to three Sr2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to three Sr2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one P5+ atom.

36 MATERIALS SCIENCE↗