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DOE OSTI2020

Materials Data on K3Na by Materials Project

K3Na crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 12-coordinate geometry to eight K and two equivalent Na atoms. There are a spread of K–K bond distances ranging from 4.39–4.66 Å. Both K–Na bond lengths are 4.36 Å. In the second K site, K is bonded in a 12-coordinate geometry to eight K and two equivalent Na atoms. There are a spread of K–K bond distances ranging from 4.39–4.66 Å. Both K–Na bond lengths are 4.36 Å. In the third K site, K is bonded in a 12-coordinate geometry to eight K and two equivalent Na atoms. There are two shorter (4.39 Å) and two longer (4.66 Å) K–K bond lengths. Both K–Na bond lengths are 4.36 Å. In the fourth K site, K is bonded in a 12-coordinate geometry to eight K and two equivalent Na atoms. Both K–Na bond lengths are 4.36 Å. Na is bonded in a 12-coordinate geometry to six K atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4UC2O11 by Materials Project

K4UC2O11 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded to eight O atoms to form distorted KO8 hexagonal bipyramids that share corners with two equivalent KO8 hexagonal bipyramids and corners with four equivalent UO8 hexagonal bipyramids. There are a spread of K–O bond distances ranging from 2.69–3.05 Å. In the second K site, K is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of K–O bond distances ranging from 2.74–3.21 Å. In the third K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.66–3.14 Å. In the fourth K site, K is bonded in a 9-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.72–3.14 Å. U is bonded to eight O atoms to form distorted UO8 hexagonal bipyramids that share corners with four equivalent KO8 hexagonal bipyramids. There are a spread of U–O bond distances ranging from 1.85–2.45 Å. There are two inequivalent C sites. In the first C site, C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.27–1.33 Å. In the second C site, C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.26–1.33 Å. There are eleven inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two K, one U, and one O atom. The O–O bond length is 1.38 Å. In the second O site, O is bonded in a distorted single-bond geometry to three K, one U, and one C atom. In the third O site, O is bonded in a 1-coordinate geometry to three K and one U atom. In the fourth O site, O is bonded in a 4-coordinate geometry to four K atoms. In the fifth O site, O is bonded in a distorted single-bond geometry to two K and one U atom. In the sixth O site, O is bonded in a distorted single-bond geometry to two equivalent K, one U, and one C atom. In the seventh O site, O is bonded in a distorted single-bond geometry to three K and one C atom. In the eighth O site, O is bonded in a distorted single-bond geometry to three K and one C atom. In the ninth O site, O is bonded in a distorted single-bond geometry to three K, one U, and one C atom. In the tenth O site, O is bonded in a distorted single-bond geometry to three K, one U, and one C atom. In the eleventh O site, O is bonded in a 5-coordinate geometry to three K, one U, and one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2YbGe4O11 by Materials Project

K2YbGe4O11 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.81–2.90 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.80–2.98 Å. In the third K site, K is bonded in a 6-coordinate geometry to four O atoms. There are two shorter (2.79 Å) and two longer (2.93 Å) K–O bond lengths. In the fourth K site, K is bonded in a 5-coordinate geometry to five O atoms. There are a spread of K–O bond distances ranging from 2.66–3.05 Å. Yb is bonded to six O atoms to form YbO6 octahedra that share corners with two equivalent YbO6 octahedra and corners with four GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 27–46°. There are a spread of Yb–O bond distances ranging from 2.25–2.32 Å. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Ge–O bond distances ranging from 1.73–1.79 Å. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Ge–O bond distances ranging from 1.73–1.80 Å. In the third Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Ge–O bond distances ranging from 1.72–1.80 Å. In the fourth Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 10°. There are a spread of Ge–O bond distances ranging from 1.72–1.80 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one K and two equivalent Ge atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Ge atoms. In the third O site, O is bonded in a 2-coordinate geometry to one K, one Yb, and one Ge atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two K, one Yb, and one Ge atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to one K and two equivalent Ge atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one K and two Ge atoms. In the seventh O site, O is bonded in a bent 150 degrees geometry to two equivalent Ge atoms. In the eighth O site, O is bonded in a 4-coordinate geometry to two equivalent K, one Yb, and one Ge atom. In the ninth O site, O is bonded in a bent 120 degrees geometry to two equivalent Ge atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Yb atoms. In the eleventh O site, O is bonded in a 3-coordinate geometry to one K and two Ge atoms. In the twelfth O site, O is bonded in a 2-coordinate geometry to one K, one Yb, and one Ge atom. In the thirteenth O site, O is bonded in a 2-coordinate geometry to one K and two Ge atoms. In the fourteenth O site, O is bonded in a 4-coordinate geometry to two K and two equivalent Yb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3NaCe(CO5)3 by Materials Project

K3NaCe(CO5)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.67–3.27 Å. In the second K site, K is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.73–3.20 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.72–3.25 Å. Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.26–2.60 Å. Ce is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Ce–O bond distances ranging from 2.39–2.56 Å. There are three inequivalent C sites. In the first C site, C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.26–1.33 Å. In the second C site, C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.28–1.31 Å. In the third C site, C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.26–1.32 Å. There are fifteen inequivalent O sites. In the first O site, O is bonded to one Na, two equivalent Ce, and one O atom to form distorted edge-sharing ONaCe2O tetrahedra. The O–O bond length is 1.40 Å. In the second O site, O is bonded in a 5-coordinate geometry to one K, one Na, two equivalent Ce, and one O atom. In the third O site, O is bonded in a 1-coordinate geometry to two K, one Ce, and one C atom. In the fourth O site, O is bonded in a 1-coordinate geometry to two K, one Ce, and one C atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Na, and one C atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one K, one Ce, and one C atom. In the seventh O site, O is bonded in a distorted single-bond geometry to two K and one C atom. In the eighth O site, O is bonded in a 1-coordinate geometry to one K, one Ce, and one C atom. In the ninth O site, O is bonded in a distorted single-bond geometry to two equivalent K, one Ce, and one C atom. In the tenth O site, O is bonded in a 1-coordinate geometry to one K, one Na, one Ce, and one C atom. In the eleventh O site, O is bonded in a 4-coordinate geometry to two K, one Na, and one C atom. In the twelfth O site, O is bonded in a distorted trigonal planar geometry to three K atoms. In the thirteenth O site, O is bonded in a trigonal non-coplanar geometry to two K and one O atom. The O–O bond length is 1.24 Å. In the fourteenth O site, O is bonded in a T-shaped geometry to three K atoms. In the fifteenth O site, O is bonded in a distorted T-shaped geometry to two K and one Na atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Zr4Si12HO44 by Materials Project

(K3Zr4Si12HO41)2(O2)3 crystallizes in the triclinic P1 space group. The structure is three-dimensional and consists of one trioxidane molecule and one K3Zr4Si12HO41 framework. In the K3Zr4Si12HO41 framework, there are three inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to six O atoms. There are a spread of K–O bond distances ranging from 2.77–2.96 Å. In the second K site, K is bonded in a 4-coordinate geometry to four O atoms. There are a spread of K–O bond distances ranging from 2.81–2.93 Å. In the third K site, K is bonded in a 7-coordinate geometry to four O atoms. There are a spread of K–O bond distances ranging from 2.77–2.88 Å. There are four inequivalent Zr sites. In the first Zr site, Zr is bonded to six O atoms to form distorted ZrO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 1.99–2.40 Å. In the second Zr site, Zr is bonded to six O atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.05–2.26 Å. In the third Zr site, Zr is bonded to six O atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.03–2.24 Å. In the fourth Zr site, Zr is bonded to six O atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.04–2.31 Å. There are twelve inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–54°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–53°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–56°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fourth Si site, Si is bonded to five O atoms to form SiO5 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–55°. There are a spread of Si–O bond distances ranging from 1.64–2.46 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–43°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–45°. There is two shorter (1.62 Å) and two longer (1.65 Å) Si–O bond length. In the seventh Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO5 tetrahedra. The corner-sharing octahedra tilt angles range from 38–43°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the eighth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–43°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the ninth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–48°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. In the tenth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–41°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the eleventh Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–41°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the twelfth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two ZrO6 octahedra and corners with two SiO5 tetrahedra. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. There are forty-one inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the second O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the third O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the fourth O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the fifth O site, O is bonded in a 1-coordinate geometry to one Si and one O atom. The O–O bond length is 2.08 Å. In the sixth O site, O is bonded in a distorted single-bond geometry to one O atom. The O–O bond length is 2.00 Å. In the seventh O site, O is bonded in a bent 120 degrees geometry to one K and one O atom. The O–O bond length is 1.29 Å. In the eighth O site, O is bonded in a 2-coordinate geometry to one Zr, one Si, and one H atom. In the ninth O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the tenth O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the eleventh O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the twelfth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the thirteenth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the fourteenth O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the fifteenth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the sixteenth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the seventeenth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Si atoms. In the eighteenth O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the nineteenth O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the twentieth O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.29 Å. In the twenty-first O site, O is bonded in a bent 120 degrees geometry to two O atoms. In the twenty-second O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the twenty-third O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the twenty-fourth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the twenty-fifth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the twenty-sixth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the twenty-seventh O site, O is bonded in a 3-coordinate geometry to one K, one Zr, and one Si atom. In the twenty-eighth O site, O is bonded in a 2-coordinate geometry to one K, one Zr, and one Si atom. In the twenty-ninth O site, O is bonded in a 2-coordinate geometry to one K, one Zr, and one Si atom. In the thirtieth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Si atoms. In the thirty-first O site, O is bonded in a distorted trigonal planar geometry to one K and two Si atoms. In the thirty-second O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the thirty-third O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Si atoms. In the thirty-fourth O site, O is bonded in a bent 120 degrees geometry to one Zr and one Si atom. In the thirty-fifth O site, O is bonded in a bent 120 degrees geometry to one Zr and one Si atom. In the thirty-sixth O site, O is bonded in a distorted bent 120 degrees geometry to one Zr, one Si, and one O atom. In the thirty-seventh O site, O is bonded in a distorted bent 120 degrees geometry to one Zr, one Si, and one O atom. In the thirty-eighth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the thirty-ninth O site, O is bonded in a distorted bent 120 degrees geometry to one Zr and one Si atom. In the fortieth O site, O is bonded in a distorted bent 150 degrees geometry to one Zr and one Si atom. In the forty-first O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2ScSi2O7 by Materials Project

K2ScSi2O7 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 3-coordinate geometry to three O atoms. There are two shorter (2.67 Å) and one longer (2.80 Å) K–O bond lengths. In the second K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.81–3.09 Å. In the third K site, K is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.87–3.27 Å. In the fourth K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.81–3.07 Å. Sc is bonded to six O atoms to form ScO6 octahedra that share corners with two equivalent ScO6 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–17°. There are a spread of Sc–O bond distances ranging from 2.09–2.16 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent ScO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–32°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent ScO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 5–35°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to two K, one Sc, and one Si atom. In the second O site, O is bonded in a 2-coordinate geometry to two equivalent K and two equivalent Si atoms. In the third O site, O is bonded in a distorted linear geometry to three K, one Sc, and one Si atom. In the fourth O site, O is bonded in a 2-coordinate geometry to two equivalent K and two equivalent Si atoms. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to two K and two equivalent Si atoms. In the sixth O site, O is bonded in a distorted linear geometry to two K, one Sc, and one Si atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to two K and two equivalent Si atoms. In the eighth O site, O is bonded in a distorted linear geometry to one K and two equivalent Sc atoms. In the ninth O site, O is bonded in a 2-coordinate geometry to two K, one Sc, and one Si atom. In the tenth O site, O is bonded in a distorted T-shaped geometry to one K and two equivalent Sc atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Te(PO7)2 by Materials Project

K3Te(PO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.77–3.18 Å. In the second K site, K is bonded to seven O atoms to form distorted KO7 pentagonal bipyramids that share corners with two equivalent TeO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one TeO6 octahedra, and edges with two equivalent KO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–42°. There are a spread of K–O bond distances ranging from 2.70–3.02 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.67–3.20 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent KO7 pentagonal bipyramids and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO7 pentagonal bipyramid and a cornercorner with one PO4 tetrahedra. There is three shorter (1.52 Å) and one longer (1.67 Å) P–O bond length. There are two inequivalent Te sites. In the first Te site, Te is bonded to six O atoms to form TeO6 octahedra that share corners with four equivalent KO7 pentagonal bipyramids and edges with two equivalent KO7 pentagonal bipyramids. There is two shorter (1.92 Å) and four longer (1.93 Å) Te–O bond length. In the second Te site, Te is bonded in an octahedral geometry to six O atoms. All Te–O bond lengths are 1.93 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal non-coplanar geometry to two K and one Te atom. In the second O site, O is bonded in a 1-coordinate geometry to two equivalent K and one Te atom. In the third O site, O is bonded in a 3-coordinate geometry to two K and one Te atom. In the fourth O site, O is bonded in a 3-coordinate geometry to two K and one Te atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one K and one Te atom. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and one Te atom. In the seventh O site, O is bonded in a single-bond geometry to one P and one O atom. The O–O bond length is 1.99 Å. In the eighth O site, O is bonded in a distorted single-bond geometry to two equivalent K and one P atom. In the ninth O site, O is bonded in a distorted linear geometry to one K and one P atom. In the tenth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two P atoms. In the eleventh O site, O is bonded in a distorted single-bond geometry to two K and one P atom. In the twelfth O site, O is bonded in a distorted single-bond geometry to two K and one P atom. In the thirteenth O site, O is bonded in a distorted single-bond geometry to one K and one P atom. In the fourteenth O site, O is bonded in a 3-coordinate geometry to two K and one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K23(Sn3Au4)3 by Materials Project

K23(Au4Sn3)3 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to four Au and two Sn atoms. There are a spread of K–Au bond distances ranging from 3.17–3.72 Å. There are one shorter (3.74 Å) and one longer (3.85 Å) K–Sn bond lengths. In the second K site, K is bonded in a 3-coordinate geometry to two equivalent Au and three Sn atoms. There are one shorter (3.38 Å) and one longer (3.45 Å) K–Au bond lengths. There are a spread of K–Sn bond distances ranging from 3.56–4.09 Å. In the third K site, K is bonded in a 4-coordinate geometry to four equivalent Au atoms. All K–Au bond lengths are 3.42 Å. In the fourth K site, K is bonded in a 3-coordinate geometry to two equivalent Au and two equivalent Sn atoms. Both K–Au bond lengths are 3.48 Å. There are one shorter (3.44 Å) and one longer (4.06 Å) K–Sn bond lengths. In the fifth K site, K is bonded in a 4-coordinate geometry to four equivalent Sn atoms. All K–Sn bond lengths are 3.95 Å. There are two inequivalent Au sites. In the first Au site, Au is bonded in a 7-coordinate geometry to five K and two Sn atoms. There are one shorter (2.71 Å) and one longer (2.73 Å) Au–Sn bond lengths. In the second Au site, Au is bonded in a 7-coordinate geometry to five K and two Sn atoms. There are one shorter (2.75 Å) and one longer (2.81 Å) Au–Sn bond lengths. There are three inequivalent Sn sites. In the first Sn site, Sn is bonded in a distorted tetrahedral geometry to four equivalent Au atoms. In the second Sn site, Sn is bonded in a 4-coordinate geometry to six K and three Au atoms. In the third Sn site, Sn is bonded in a 2-coordinate geometry to eight K and two equivalent Au atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Potassium isotopic fractionation in a humid and an arid soil–plant system in Hawai‘i

Plants play a critical role in the cycling of potassium (K) and the fractionation of its isotopes. However, little is known about K stable isotopic compositions in natural soil–plant systems and possible fractionation during intra-plant transport and root-soil uptake of K. Herein this study focuses on K isotopic fractionation within a humid and an arid soil–plant system sampled on the windward and leeward sides of Kohala Mountain, Hawai‘i. We determined the K isotopic compositions of < 2-mm bulk soil, soil saturation extraction, and selected plant tissues by multi-collector inductively coupled plasma mass spectrometry and X-ray absorption spectroscopy. We studied soils and individual tissue samples such as roots, stems, barks, shoots (a sum of stems and fresh leaves), leaves (fresh and dead), seeds, and flowers of trees and grasses. The results demonstrated that: (i) tissue δ 41 K values ranged from –1.06 ± 0.06 to 1.15 ± 0.09‰; (ii) within the same plant, stems (barks), dead leaves, and reproductive tissues (flowers and seeds) were isotopically lighter compared to fresh leaves, and to a lesser extent, roots; (iii) δ 41 K values of the humid soil (-0.54 ± 0.07 to –0.49 ± 0.06‰) were lower than those of the arid soil (-0.24 ± 0.07 to –0.14 ± 0.06‰); and (iv) soil bioavailable pool δ 41 K (saturation extracts) ranged from –0.63 ± 0.08 to 0.34 ± 0.08‰ and 0.48 ± 0.08 to 0.54 ± 0.10‰ in the humid and arid soils, respectively. From synchrotron-based analysis of K atoms, we identified two major K-bearing phases co-existing as ionic K + and K-pectate association of different fractions. Based on K isotopic and synchrotron data, we conclude that two dominant processes are responsible for plant-mediated K isotopic fractionation, including (1) K redistribution during intra-plant circulation and (2) uptake at the root-soil interface. For intra-plant circulation of K, there is a high affinity of isotopically lighter K to organic complexes as K-pectate, and K-pectate is particularly enriched in roots and fresh leaves. For K uptake at root-soil interface, isotopically lighter K is preferentially taken by roots from soil bioavailable pools following a low-affinity (passive) transport path. Soil K budget in two sites reflects strong source mixing effects with limited plant imprints. This work provides exploratory data on the biogeochemical fractionation of K isotopes in the soil–plant system.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Materials Data on K5SnBi3 by Materials Project

K5SnBi3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded to four Bi atoms to form a mixture of distorted edge and corner-sharing KBi4 tetrahedra. There are a spread of K–Bi bond distances ranging from 3.61–3.83 Å. In the second K site, K is bonded in a distorted see-saw-like geometry to four Bi atoms. There are a spread of K–Bi bond distances ranging from 3.62–3.86 Å. In the third K site, K is bonded in a 4-coordinate geometry to one Sn and three Bi atoms. The K–Sn bond length is 3.91 Å. There are a spread of K–Bi bond distances ranging from 3.66–3.79 Å. In the fourth K site, K is bonded to four Bi atoms to form a mixture of distorted edge and corner-sharing KBi4 tetrahedra. There are a spread of K–Bi bond distances ranging from 3.60–3.63 Å. In the fifth K site, K is bonded in a 6-coordinate geometry to two equivalent Sn and four Bi atoms. There are one shorter (3.89 Å) and one longer (3.94 Å) K–Sn bond lengths. There are a spread of K–Bi bond distances ranging from 3.71–4.07 Å. Sn is bonded in a 7-coordinate geometry to three K and four Bi atoms. There are a spread of Sn–Bi bond distances ranging from 2.96–3.05 Å. There are three inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to seven K and one Sn atom. In the second Bi site, Bi is bonded in a 7-coordinate geometry to five K and two equivalent Sn atoms. In the third Bi site, Bi is bonded in a 8-coordinate geometry to seven K and one Sn atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4Sn9 by Materials Project

K4Sn9 is Magnesium tetraboride-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven Sn atoms. There are a spread of K–Sn bond distances ranging from 3.66–4.02 Å. In the second K site, K is bonded in a 7-coordinate geometry to seven Sn atoms. There are a spread of K–Sn bond distances ranging from 3.51–4.07 Å. In the third K site, K is bonded in a 8-coordinate geometry to nine Sn atoms. There are a spread of K–Sn bond distances ranging from 3.59–4.12 Å. In the fourth K site, K is bonded in a 3-coordinate geometry to eight Sn atoms. There are a spread of K–Sn bond distances ranging from 3.61–4.12 Å. There are nine inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to three K and five Sn atoms. There are a spread of Sn–Sn bond distances ranging from 3.03–3.29 Å. In the second Sn site, Sn is bonded in a 8-coordinate geometry to four K and four Sn atoms. There are a spread of Sn–Sn bond distances ranging from 3.01–3.06 Å. In the third Sn site, Sn is bonded in a 8-coordinate geometry to three K and five Sn atoms. There are a spread of Sn–Sn bond distances ranging from 2.99–3.21 Å. In the fourth Sn site, Sn is bonded in a 2-coordinate geometry to three K and five Sn atoms. There are a spread of Sn–Sn bond distances ranging from 2.98–3.38 Å. In the fifth Sn site, Sn is bonded in a 8-coordinate geometry to four K and four Sn atoms. There are one shorter (2.99 Å) and one longer (3.04 Å) Sn–Sn bond lengths. In the sixth Sn site, Sn is bonded in a 1-coordinate geometry to four K and four Sn atoms. The Sn–Sn bond length is 3.01 Å. In the seventh Sn site, Sn is bonded in a 8-coordinate geometry to four K and four Sn atoms. There are one shorter (2.98 Å) and one longer (3.04 Å) Sn–Sn bond lengths. In the eighth Sn site, Sn is bonded in a 6-coordinate geometry to two K and four Sn atoms. In the ninth Sn site, Sn is bonded in a 9-coordinate geometry to four K and five Sn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Al2Si4O13 by Materials Project

K3Al2Si4O13 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.78–3.22 Å. In the second K site, K is bonded in a 6-coordinate geometry to six O atoms. There are a spread of K–O bond distances ranging from 2.71–3.04 Å. In the third K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.83–3.06 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.77 Å. In the second Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.78 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are thirteen inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one K and two Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to one K, one Al, and one Si atom. In the third O site, O is bonded in a bent 150 degrees geometry to one K, one Al, and one Si atom. In the fourth O site, O is bonded in a distorted single-bond geometry to three K and one Si atom. In the fifth O site, O is bonded in a 2-coordinate geometry to two K, one Al, and one Si atom. In the sixth O site, O is bonded in a 4-coordinate geometry to two K, one Al, and one Si atom. In the seventh O site, O is bonded in a distorted single-bond geometry to three K and one Si atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the ninth O site, O is bonded in a 2-coordinate geometry to one K and two Si atoms. In the tenth O site, O is bonded in a 2-coordinate geometry to two equivalent K, one Al, and one Si atom. In the eleventh O site, O is bonded in a 2-coordinate geometry to one K, one Al, and one Si atom. In the twelfth O site, O is bonded in a 2-coordinate geometry to two K, one Al, and one Si atom. In the thirteenth O site, O is bonded in a distorted bent 150 degrees geometry to two K and two Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Tl(Cl3O)2 by Materials Project

K21Tl7(OCl7)6(O2)4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of sixteen water molecules and one K21Tl7(OCl7)6 framework. In the K21Tl7(OCl7)6 framework, there are four inequivalent K sites. In the first K site, K is bonded in an octahedral geometry to six O atoms. There are four shorter (2.85 Å) and two longer (2.98 Å) K–O bond lengths. In the second K site, K is bonded in a 8-coordinate geometry to eight Cl atoms. There are a spread of K–Cl bond distances ranging from 3.06–3.73 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight Cl atoms. There are a spread of K–Cl bond distances ranging from 3.22–3.59 Å. In the fourth K site, K is bonded in a 1-coordinate geometry to one O and seven Cl atoms. The K–O bond length is 2.85 Å. There are a spread of K–Cl bond distances ranging from 3.25–3.50 Å. There are three inequivalent Tl sites. In the first Tl site, Tl is bonded in an octahedral geometry to six Cl atoms. There are four shorter (2.56 Å) and two longer (3.09 Å) Tl–Cl bond lengths. In the second Tl site, Tl is bonded in an octahedral geometry to six Cl atoms. There are two shorter (2.52 Å) and four longer (2.69 Å) Tl–Cl bond lengths. In the third Tl site, Tl is bonded in an octahedral geometry to six Cl atoms. There are two shorter (2.64 Å) and four longer (2.65 Å) Tl–Cl bond lengths. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one K atom. In the second O site, O is bonded in a trigonal planar geometry to three K atoms. There are seven inequivalent Cl sites. In the first Cl site, Cl is bonded to five K and one Tl atom to form distorted ClK5Tl octahedra that share corners with two equivalent ClK5Tl octahedra, corners with four equivalent ClK4Tl square pyramids, edges with two equivalent ClK4Tl square pyramids, faces with two equivalent ClK5Tl octahedra, and faces with two equivalent ClK4Tl square pyramids. The corner-sharing octahedra tilt angles range from 0–33°. In the second Cl site, Cl is bonded to four K and one Tl atom to form distorted ClK4Tl square pyramids that share corners with four equivalent ClK5Tl octahedra, a cornercorner with one ClK4Tl square pyramid, edges with two equivalent ClK5Tl octahedra, and edges with four ClK4Tl square pyramids. The corner-sharing octahedra tilt angles range from 49–51°. In the third Cl site, Cl is bonded in a 4-coordinate geometry to three K and one Tl atom. In the fourth Cl site, Cl is bonded in a distorted see-saw-like geometry to three K and one Tl atom. In the fifth Cl site, Cl is bonded in a distorted single-bond geometry to one Tl atom. In the sixth Cl site, Cl is bonded in a 5-coordinate geometry to four K and one Tl atom. In the seventh Cl site, Cl is bonded to four K and one Tl atom to form distorted ClK4Tl square pyramids that share a cornercorner with one ClK4Tl square pyramid, edges with four equivalent ClK4Tl square pyramids, and faces with four equivalent ClK5Tl octahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2Zn4P4O21 by Materials Project

(KZn2(PO5)2)4O2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of one hydrogen peroxide molecule and one KZn2(PO5)2 framework. In the KZn2(PO5)2 framework, there are two inequivalent K sites. In the first K site, K is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of K–O bond distances ranging from 2.72–3.24 Å. In the second K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.88–3.32 Å. There are four inequivalent Zn sites. In the first Zn site, Zn is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Zn–O bond distances ranging from 1.88–2.06 Å. In the second Zn site, Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.93–1.98 Å. In the third Zn site, Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.92–2.00 Å. In the fourth Zn site, Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.93–2.03 Å. There are four inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three ZnO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three ZnO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four ZnO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two ZnO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. There are twenty inequivalent O sites. In the first O site, O is bonded in a distorted T-shaped geometry to two equivalent Zn and one P atom. In the second O site, O is bonded in a 3-coordinate geometry to one K, one Zn, and one P atom. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Zn, and one P atom. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Zn, and one P atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one K and one P atom. In the sixth O site, O is bonded in a 2-coordinate geometry to one K, one Zn, and one P atom. In the seventh O site, O is bonded in a distorted bent 120 degrees geometry to one Zn and one P atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one K, one Zn, and one P atom. In the ninth O site, O is bonded in a 2-coordinate geometry to one K, one Zn, and one P atom. In the tenth O site, O is bonded in a distorted bent 150 degrees geometry to one Zn and one P atom. In the eleventh O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Zn, and one P atom. In the twelfth O site, O is bonded in a 2-coordinate geometry to one K, one Zn, and one P atom. In the thirteenth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Zn, and one P atom. In the fourteenth O site, O is bonded in a 2-coordinate geometry to one K, one Zn, and one P atom. In the fifteenth O site, O is bonded in a distorted water-like geometry to one K and one P atom. In the sixteenth O site, O is bonded in a bent 150 degrees geometry to one Zn and one P atom. In the seventeenth O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.24 Å. In the eighteenth O site, O is bonded in a single-bond geometry to one K and one Zn atom. In the nineteenth O site, O is bonded in a water-like geometry to one K and one O atom. In the twentieth O site, O is bonded in a water-like geometry to two K atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3TeP3O17 by Materials Project

K3Te(PO5)3O2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of four oxygen molecules and one K3Te(PO5)3 framework. In the K3Te(PO5)3 framework, there are three inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.73–2.97 Å. In the second K site, K is bonded to seven O atoms to form distorted KO7 pentagonal bipyramids that share corners with two equivalent KO7 pentagonal bipyramids, a cornercorner with one TeO4 tetrahedra, and corners with six PO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.84–3.19 Å. In the third K site, K is bonded in a 5-coordinate geometry to five O atoms. There are a spread of K–O bond distances ranging from 2.64–3.16 Å. There are three inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO7 pentagonal bipyramid and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent KO7 pentagonal bipyramids and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three equivalent KO7 pentagonal bipyramids and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.66 Å. Te is bonded to four O atoms to form TeO4 tetrahedra that share a cornercorner with one KO7 pentagonal bipyramid. There is two shorter (1.82 Å) and two longer (1.88 Å) Te–O bond length. There are fifteen inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one K and one Te atom. In the second O site, O is bonded in a linear geometry to one K and one Te atom. In the third O site, O is bonded in a distorted trigonal non-coplanar geometry to two K and one Te atom. In the fourth O site, O is bonded in a water-like geometry to one K and one O atom. The O–O bond length is 1.23 Å. In the fifth O site, O is bonded in a linear geometry to one K and one Te atom. In the sixth O site, O is bonded in a distorted single-bond geometry to two K and one P atom. In the seventh O site, O is bonded in a distorted bent 120 degrees geometry to one K and one P atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one K and one P atom. In the ninth O site, O is bonded in a distorted single-bond geometry to three K and one P atom. In the tenth O site, O is bonded in a distorted single-bond geometry to three K and one P atom. In the eleventh O site, O is bonded in a distorted single-bond geometry to two K and one P atom. In the twelfth O site, O is bonded in a bent 120 degrees geometry to two P atoms. In the thirteenth O site, O is bonded in a bent 120 degrees geometry to two P atoms. In the fourteenth O site, O is bonded in a 2-coordinate geometry to one K and two P atoms. In the fifteenth O site, O is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Tl(Cl3O)2 by Materials Project

K21Tl7(OCl7)6(O2)4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of four 1,2,3,4-tetraoxacyclobutane molecules and one K21Tl7(OCl7)6 framework. In the K21Tl7(OCl7)6 framework, there are four inequivalent K sites. In the first K site, K is bonded in an octahedral geometry to six O atoms. There are two shorter (2.55 Å) and four longer (2.90 Å) K–O bond lengths. In the second K site, K is bonded to six Cl atoms to form distorted KCl6 pentagonal pyramids that share corners with four TlCl6 octahedra, corners with two equivalent KCl6 pentagonal pyramids, and an edgeedge with one TlCl6 octahedra. The corner-sharing octahedra tilt angles range from 28–56°. There are a spread of K–Cl bond distances ranging from 3.06–3.37 Å. In the third K site, K is bonded in a 6-coordinate geometry to six Cl atoms. There are a spread of K–Cl bond distances ranging from 3.18–3.34 Å. In the fourth K site, K is bonded in a 8-coordinate geometry to one O and seven Cl atoms. The K–O bond length is 2.91 Å. There are a spread of K–Cl bond distances ranging from 3.18–3.59 Å. There are three inequivalent Tl sites. In the first Tl site, Tl is bonded to six Cl atoms to form TlCl6 octahedra that share edges with four equivalent KCl6 pentagonal pyramids. There are two shorter (2.40 Å) and four longer (2.79 Å) Tl–Cl bond lengths. In the second Tl site, Tl is bonded to six Cl atoms to form TlCl6 octahedra that share corners with four equivalent KCl6 pentagonal pyramids. There are two shorter (2.55 Å) and four longer (2.67 Å) Tl–Cl bond lengths. In the third Tl site, Tl is bonded to six Cl atoms to form TlCl6 octahedra that share corners with two equivalent KCl6 pentagonal pyramids. There are a spread of Tl–Cl bond distances ranging from 2.60–2.72 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one K atom. In the second O site, O is bonded in a trigonal planar geometry to three K atoms. There are seven inequivalent Cl sites. In the first Cl site, Cl is bonded in a 4-coordinate geometry to three K and one Tl atom. In the second Cl site, Cl is bonded to four K and one Tl atom to form a mixture of distorted edge and corner-sharing ClK4Tl square pyramids. In the third Cl site, Cl is bonded in a distorted trigonal non-coplanar geometry to two equivalent K and one Tl atom. In the fourth Cl site, Cl is bonded in a distorted see-saw-like geometry to three K and one Tl atom. In the fifth Cl site, Cl is bonded in a single-bond geometry to one Tl atom. In the sixth Cl site, Cl is bonded to four K and one Tl atom to form a mixture of edge and corner-sharing ClK4Tl trigonal bipyramids. In the seventh Cl site, Cl is bonded to four K and one Tl atom to form a mixture of edge and corner-sharing ClK4Tl square pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2V3P2O13F2 by Materials Project

K2V3P2O13F2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 10-coordinate geometry to eight O and two F atoms. There are a spread of K–O bond distances ranging from 2.83–3.27 Å. There are one shorter (2.80 Å) and one longer (2.81 Å) K–F bond lengths. In the second K site, K is bonded in a 3-coordinate geometry to seven O and two F atoms. There are a spread of K–O bond distances ranging from 2.76–3.23 Å. There are one shorter (2.77 Å) and one longer (3.23 Å) K–F bond lengths. There are three inequivalent V sites. In the first V site, V is bonded to five O and one F atom to form distorted VO5F octahedra that share corners with four PO4 tetrahedra and a faceface with one VO5F octahedra. There are a spread of V–O bond distances ranging from 1.64–2.14 Å. The V–F bond length is 2.11 Å. In the second V site, V is bonded in a 6-coordinate geometry to four O and two equivalent F atoms. There are a spread of V–O bond distances ranging from 1.66–2.20 Å. There are one shorter (1.97 Å) and one longer (2.29 Å) V–F bond lengths. In the third V site, V is bonded to five O and one F atom to form distorted VO5F octahedra that share corners with four PO4 tetrahedra and a faceface with one VO5F octahedra. There are a spread of V–O bond distances ranging from 1.61–2.09 Å. The V–F bond length is 2.11 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four VO5F octahedra. The corner-sharing octahedra tilt angles range from 33–57°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four VO5F octahedra. The corner-sharing octahedra tilt angles range from 31–55°. There are a spread of P–O bond distances ranging from 1.49–1.60 Å. There are thirteen inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one K, one V, and one P atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one K, one V, and one P atom. In the third O site, O is bonded in a 3-coordinate geometry to two V and one P atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one K, one V, and one P atom. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one V, and one P atom. In the sixth O site, O is bonded in a 1-coordinate geometry to one K, one V, and one P atom. In the seventh O site, O is bonded in a 3-coordinate geometry to two V and one P atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one V, and one P atom. In the ninth O site, O is bonded in a single-bond geometry to two K and one V atom. In the tenth O site, O is bonded in a distorted single-bond geometry to three K and one V atom. In the eleventh O site, O is bonded in a single-bond geometry to two K and one V atom. In the twelfth O site, O is bonded in a single-bond geometry to one K and one V atom. In the thirteenth O site, O is bonded in a single-bond geometry to one K atom. There are two inequivalent F sites. In the first F site, F is bonded in a 1-coordinate geometry to two K and two equivalent V atoms. In the second F site, F is bonded in a distorted trigonal pyramidal geometry to two K and two V atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2024

X-ray absorption spectroscopy and theoretical investigations of the effect of extended ligands in potassium organic matter interaction

Potassium (K) is an essential nutrient for plant growth, and despite its abundance in soil, most of the K is structurally bound in minerals, limiting its bioavailability and making this soil K reservoir largely inaccessible to plants. Microbial biochemical weathering has been shown to be a promising pathway to sustainably increase plant available K. However, the mechanisms underpinning microbial K uptake, transformation, storage, and sharing are poorly resolved. Here, to better understand the controls on microbial K transformations, we performed K K-edge x-ray absorption near-edge structure (XANES) spectroscopy on K-organic salts, including acetate, citrate, nitrate, oxalate, and tartrate, which are frequently observed as low molecular weight organic acids secreted by soil microbes, as well as humic acid, which acts as a proxy for higher molecular weight organic acids. The organic salts display feature-rich K XANES spectra, each demonstrating numerous unique features spanning ~13 eV range across the absorption edge. In contrast, the spectra for humic acid have one broad, wide feature across the same energy range. We used a combination of time-dependent density functional theory and the Bethe–Salpeter equation based approach within the OCEAN code to simulate the experimental spectra for K-nitrate (KNO 3 ) and K-citrate [K 3 (C 6 H 5 O 7 )·H 2 O] to identify the electronic transitions that give rise to some of the outlying and unique spectral features in the organic salts. KNO 3 has both the lowest and highest lying energy features, and K 3 (C 6 H 5 O 7 )·H 2 O is produced by several soil microbes and is effective at mineral weathering. Our results analyze the K-organic salt bonding in detail to elucidate why the spectral shapes differ and indicate that the K K-edge XANES spectra are associated with the entire ligand despite similar first-shell bonding environments around the K center. The improved understanding of K bonding environments with organic ligands and their use for interpretation of the K-XANES spectra provides an important toolkit to understand how K is transformed by microbial processes and made bioavailable for plant uptake.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗