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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Li5Fe2(PO4)3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twenty inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two FeO6 octahedra, a cornercorner with one LiO4 tetrahedra, and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 71–74°. There are a spread of Li–O bond distances ranging from 1.98–2.11 Å. In the second Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.98–2.08 Å. In the third Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 2.00–2.12 Å. In the fourth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.97–2.16 Å. In the fifth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, and edges with two FeO6 octahedra. There are a spread of Li–O bond distances ranging from 1.92–2.10 Å. In the sixth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.91–2.10 Å. In the seventh Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.98–2.17 Å. In the eighth Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.99–2.11 Å. In the ninth Li1+ site, Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.98–2.08 Å. In the tenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two FeO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 72–74°. There are a spread of Li–O bond distances ranging from 1.98–2.12 Å. In the eleventh Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two FeO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 67–81°. There are a spread of Li–O bond distances ranging from 1.94–2.57 Å. In the twelfth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four PO4 tetrahedra and an edgeedge with one FeO6 octahedra. There are a spread of Li–O bond distances ranging from 1.99–2.03 Å. In the thirteenth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.04–2.53 Å. In the fourteenth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.85–2.02 Å. In the fifteenth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.85–2.13 Å. In the sixteenth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.85–2.12 Å. In the seventeenth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.85–2.01 Å. In the eighteenth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.03–2.53 Å. In the nineteenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and edges with two FeO6 octahedra. There are a spread of Li–O bond distances ranging from 1.99–2.03 Å. In the twentieth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of Li–O bond distances ranging from 1.94–2.55 Å. There are eight inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.04–2.45 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.04–2.46 Å. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Fe–O bond distances ranging from 2.12–2.33 Å. In the fourth Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Fe–O bond distances ranging from 2.12–2.32 Å. In the fifth Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra and corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.10–2.28 Å. In the sixth Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra and corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.09–2.31 Å. In the seventh Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Fe–O bond distances ranging from 2.05–2.50 Å. In the eighth Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.05–2.53 Å. There are twelve inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–52°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–56°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra, corners with two LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 32–51°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–56°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra, corners with two LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 32–51°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–53°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra, corners with two LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 31–54°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–58°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the ninth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra, a cornercorner with one LiO4 tetrahedra, and corners with two LiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 39–56°. There is two shorter (1.55 Å) and two longer (1.57 Å) P–O bond length. In the tenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–59°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the eleventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra, corners with two LiO4 tetrahedra, and corners with two LiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 39–55°. There is two shorter (1.55 Å) and two longer (1.57 Å) P–O bond length. In the twelfth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra, corners with two LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 31–54°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. There are forty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted tetrahedral geometry to two Li1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded to two Li1+, one Fe2+, and one P5+ atom to form distorted corner-sharing OLi2FeP tetrahedra. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+, one Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Li1+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+, one Fe2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Li1+, one Fe2+, and one
Apatite Ca5(PO4)3(F,Cl,OH), merrillite Ca18Na2Mg2(PO4)14, and whitlockite Ca9(Mg,Fe2+)(PO4)6[PO3(OH)] are the primary phosphate minerals found in most planetary materials including rocks from Earth, Moon, Mars, and asteroids [1-2]. For many years, the terms merrillite and whitlockite have been used interchangeably in the meteorite literature. Much of the confusion regarding the relationship between terrestrial and extraterrestrial "whitlockite" is based on the presence or absence of hydrogen in the mineral structure. Whitlockite has approximately 8500 ppm H2O, and the term "merrillite" has been adopted to identify the hydrogen-free form of whitlockite [2]. The atomic structures of merrillite and whitlockite were examined in detail by Hughes et al. [3-4]. On Earth, whitlockite has been found in rocks from evolved pegmatitic systems [2-4] and in some mantle rocks [e.g., 5]. Furthermore, terrestrial whitlockite has been shown to have some merrillite component [4]. For the meteoritic and lunar materials that have been investigated, merrillite appears to be far more common than whitlockite, and it has been proposed that the whitlockite component is unique to terrestrial samples [4]. There are some reports of "whitlockite" in the meteorite literature; however, these likely represent misidentifications of merrillite because there have been no reports of extraterrestrial whitlockite that have been verified through crystal structural studies or analyzed for their H contents. Hughes et al. [3] reported the atomic arrangement of lunar merrillite and demonstrated that the phase is similar to meteoritic merrillite and, predictably, devoid of hydrogen. In a follow-up study, Hughes et al. [4] reported the atomic arrangements of two natural samples of whitlockite, one synthetic whitlockite, and samples of synthetic whitlockite that were heated at 500degC and 1050degC for 24 h. The crystal chemistry and crystal structures of the phases were compared, and it was discovered that the latter treatment resulted in the dehydrogenation of whitlockite to form merrillite. The presence of merrillite vs. whitlockite was widely thought to serve as an indication that magmas were anhydrous [e.g., 6-7]. However, McCubbin et al., [8] determined that merrillite in the martian meteorite Shergotty had no discernible whitlockite component despite its coexistence with OH-rich apatite. Consequently, McCubbin et al., (2014) speculated that the absence of a whitlockite component in Shergotty merrillite and other planetary merrillites may be a consequence of the limited thermal stability of H in whitlockite (stable only at T less than1050degC), which would prohibit merrillite-whitlockite solid-solution at high temperatures. In the present study, we have aimed to test this hypothesis experimentally by examining the stability of whitlockite in basaltic magmas at 1.2 GPa and a temperature range of -1000- 1300degC.
LiFe4(PO4)3 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.11 Å) and two longer (2.64 Å) Li–O bond lengths. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with two equivalent FeO6 octahedra, corners with five PO4 tetrahedra, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 63°. There are a spread of Fe–O bond distances ranging from 2.04–2.20 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 pentagonal pyramids that share corners with two equivalent FeO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Fe–O bond distances ranging from 1.98–2.33 Å. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one FeO6 pentagonal pyramid, corners with four PO4 tetrahedra, a cornercorner with one FeO5 trigonal bipyramid, edges with two equivalent FeO6 octahedra, an edgeedge with one FeO6 pentagonal pyramid, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.08–2.56 Å. There are three 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 FeO6 octahedra, a cornercorner with one FeO6 pentagonal pyramid, corners with two equivalent FeO5 trigonal bipyramids, and an edgeedge with one FeO6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 60°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent FeO6 octahedra, a cornercorner with one FeO6 pentagonal pyramid, and corners with two equivalent FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of P–O bond distances ranging from 1.54–1.60 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent FeO6 pentagonal pyramids, a cornercorner with one FeO5 trigonal bipyramid, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted tetrahedral geometry to three Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, two Fe2+, and one P5+ atom.
KFe4(PO4)3 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.81–3.25 Å. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with two equivalent FeO6 octahedra, corners with five PO4 tetrahedra, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 62°. There are a spread of Fe–O bond distances ranging from 2.03–2.22 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 pentagonal pyramids that share corners with two equivalent FeO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 70°. There are a spread of Fe–O bond distances ranging from 2.01–2.37 Å. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one FeO6 pentagonal pyramid, corners with four PO4 tetrahedra, a cornercorner with one FeO5 trigonal bipyramid, edges with two equivalent FeO6 octahedra, an edgeedge with one FeO6 pentagonal pyramid, and an edgeedge with one PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.10–2.55 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent FeO6 octahedra, a cornercorner with one FeO6 pentagonal pyramid, and corners with two equivalent FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 49–56°. 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 PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent FeO6 pentagonal pyramids, a cornercorner with one FeO5 trigonal bipyramid, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, a cornercorner with one FeO6 pentagonal pyramid, corners with two equivalent FeO5 trigonal bipyramids, and an edgeedge with one FeO6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 59°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, two Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted tetrahedral geometry to three Fe2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+, one Fe2+, and one P5+ atom.
V2Fe(PO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. V+3.50+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six equivalent PO4 tetrahedra. There is three shorter (1.93 Å) and three longer (2.04 Å) V–O bond length. Fe2+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Fe–O bond lengths are 2.22 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent VO6 octahedra. The corner-sharing octahedra tilt angles range from 26–46°. There is two shorter (1.53 Å) and two longer (1.56 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one V+3.50+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one V+3.50+, one Fe2+, and one P5+ atom.
LiFe4(PO4)3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with five PO4 tetrahedra and edges with two equivalent LiO5 trigonal bipyramids. There are a spread of Li–O bond distances ranging from 1.95–2.26 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.07–2.62 Å. In the second Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.09–2.31 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 LiO5 trigonal bipyramids. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO5 trigonal bipyramid. There is three shorter (1.55 Å) and one longer (1.56 Å) P–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+, one Fe2+, and one P5+ atom to form a mixture of distorted edge and corner-sharing OLi2FeP trigonal pyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, two equivalent Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Fe2+ and one P5+ atom.
KFeCo3(PO4)3 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.18 Å. Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent CoO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of Fe–O bond distances ranging from 2.04–2.30 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to five O2- atoms to form CoO5 trigonal bipyramids that share corners with two equivalent CoO6 octahedra, corners with five PO4 tetrahedra, and an edgeedge with one CoO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 63°. There are a spread of Co–O bond distances ranging from 1.99–2.25 Å. In the second Co2+ site, Co2+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with four PO4 tetrahedra, a cornercorner with one CoO5 trigonal bipyramid, an edgeedge with one FeO6 octahedra, edges with two equivalent CoO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of Co–O bond distances ranging from 2.06–2.51 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent CoO6 octahedra, corners with two equivalent CoO5 trigonal bipyramids, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–59°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent CoO6 octahedra, a cornercorner with one CoO5 trigonal bipyramid, and edges with two equivalent CoO6 octahedra. The corner-sharing octahedra tilt angles range from 45–51°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with four equivalent CoO6 octahedra, and corners with two equivalent CoO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 50–60°. There are a spread of P–O bond distances ranging from 1.53–1.61 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, one Fe2+, one Co2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Co2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Fe2+, one Co2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent K1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Co2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted tetrahedral geometry to three Co2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Co2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Co2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Fe2+, two equivalent Co2+, and one P5+ atom.
LiFePO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.74 Å. Fe2+ is bonded to five O2- atoms to form FeO5 square pyramids that share corners with five equivalent PO4 tetrahedra and edges with two equivalent FeO5 square pyramids. There are a spread of Fe–O bond distances ranging from 2.01–2.26 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with five equivalent FeO5 square pyramids. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Li1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Li1+, one Fe2+, and one P5+ atom.
Fe3(PO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 pentagonal pyramids that share corners with two equivalent FeO6 octahedra, corners with four equivalent FeO6 pentagonal pyramids, corners with four equivalent PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 60–65°. There are a spread of Fe–O bond distances ranging from 2.07–2.42 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 pentagonal pyramids, corners with two equivalent PO4 tetrahedra, edges with two equivalent FeO6 pentagonal pyramids, and edges with two equivalent PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.13–2.22 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with four equivalent FeO6 pentagonal pyramids, an edgeedge with one FeO6 octahedra, and an edgeedge with one FeO6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 53°. There is three shorter (1.55 Å) and one longer (1.59 Å) P–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe2+ and one P5+ atom.
Fe2Ni(PO4)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six FeO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–64°. There are a spread of Fe–O bond distances ranging from 2.05–2.39 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent NiO6 octahedra, corners with two PO4 tetrahedra, an edgeedge with one FeO6 octahedra, an edgeedge with one NiO6 octahedra, and edges with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–64°. There are a spread of Fe–O bond distances ranging from 2.13–2.20 Å. Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent NiO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–64°. There are a spread of Ni–O bond distances ranging from 2.04–2.30 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 FeO6 octahedra, corners with three equivalent NiO6 octahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one NiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–57°. There is three shorter (1.55 Å) and one longer (1.60 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NiO6 octahedra, corners with four FeO6 octahedra, and edges with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 46–57°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Fe2+, one Ni2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ni2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Fe2+, two equivalent Ni2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Fe2+, one Ni2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom.
Li2Fe5(PO4)4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a 2-coordinate geometry to seven O2- atoms. There are a spread of Li–O bond distances ranging from 2.04–2.76 Å. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share corners with five PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.95–2.24 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with four PO4 tetrahedra, an edgeedge with one FeO6 octahedra, an edgeedge with one PO4 tetrahedra, and edges with two equivalent FeO5 trigonal bipyramids. There are a spread of Fe–O bond distances ranging from 2.01–2.43 Å. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.12–2.27 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 FeO6 octahedra, corners with three equivalent FeO5 trigonal bipyramids, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 46–52°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with five FeO6 octahedra and corners with two equivalent FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 40–51°. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Li1+, two Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+, two Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom.
Li4Cr2MnFe3(PO4)6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.61 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.12–2.68 Å. In the third Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.12–2.68 Å. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.13–2.67 Å. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one FeO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.10–2.32 Å. In the second Cr3+ site, Cr3+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one FeO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.11–2.35 Å. Mn2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 2.08–2.40 Å. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CrO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.94–2.11 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CrO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.93–2.10 Å. In the third Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.04–2.40 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 28–38°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 20–40°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 20–40°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 42–47°. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 43–48°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CrO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 42–48°. There is two shorter (1.53 Å) and two longer (1.58 Å) P–O bond length. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Mn2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Mn2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Mn2+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to one Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Mn2+, and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Mn2+, and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Fe2+, and one P5+ atom. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one Cr3+, one Mn2+, and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom.
Mg3Fe3(PO4)4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six PO4 tetrahedra, a cornercorner with one MgO5 trigonal bipyramid, a cornercorner with one FeO5 trigonal bipyramid, and edges with two FeO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 2.06–2.20 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six PO4 tetrahedra, corners with two FeO5 trigonal bipyramids, an edgeedge with one MgO5 trigonal bipyramid, and an edgeedge with one FeO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.08–2.20 Å. In the third Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted MgO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one MgO6 octahedra, an edgeedge with one PO4 tetrahedra, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 56°. There are a spread of Mg–O bond distances ranging from 1.99–2.14 Å. There are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one MgO6 octahedra, an edgeedge with one PO4 tetrahedra, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 59°. There are a spread of Fe–O bond distances ranging from 2.02–2.22 Å. In the second Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one MgO6 octahedra, an edgeedge with one PO4 tetrahedra, and an edgeedge with one MgO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 59°. There are a spread of Fe–O bond distances ranging from 2.02–2.21 Å. In the third Fe2+ site, Fe2+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one MgO6 octahedra, an edgeedge with one PO4 tetrahedra, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 60°. There are a spread of Fe–O bond distances ranging from 2.02–2.22 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 trigonal bipyramid, corners with two FeO5 trigonal bipyramids, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 31–51°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 trigonal bipyramid, corners with two FeO5 trigonal bipyramids, and an edgeedge with one MgO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 33–53°. There is three shorter (1.55 Å) and one longer (1.56 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 trigonal bipyramid, corners with two FeO5 trigonal bipyramids, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 33–52°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MgO6 octahedra, corners with three FeO5 trigonal bipyramids, and an edgeedge with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 32–52°. There is three shorter (1.55 Å) and one longer (1.57 Å) P–O bond length. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Fe2+, and one P5+ atom.
NaFe(PO3)3 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six PO4 tetrahedra and edges with three equivalent FeO6 octahedra. There are a spread of Na–O bond distances ranging from 2.29–2.44 Å. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and edges with three equivalent NaO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.10–2.24 Å. There are three 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 NaO6 octahedra, corners with two equivalent FeO6 octahedra, and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–60°. 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 PO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent FeO6 octahedra, and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–55°. 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 PO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent FeO6 octahedra, and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–72°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms.
Fe2P2O7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.03–2.61 Å. In the second Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.03–2.62 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 1.53–1.59 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 1.53–1.59 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Fe2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Fe2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Fe2+ and one P5+ atom.