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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
BaFeP(O2F)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ba2+ is bonded in a 10-coordinate geometry to seven O2- and three F1- atoms. There are a spread of Ba–O bond distances ranging from 2.81–3.21 Å. There are a spread of Ba–F bond distances ranging from 2.66–2.80 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- and two equivalent F1- atoms to form FeO4F2 octahedra that share corners with two equivalent FeO2F4 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are two shorter (1.97 Å) and two longer (2.05 Å) Fe–O bond lengths. Both Fe–F bond lengths are 2.02 Å. In the second Fe3+ site, Fe3+ is bonded to two equivalent O2- and four F1- atoms to form FeO2F4 octahedra that share corners with two equivalent FeO4F2 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. Both Fe–O bond lengths are 2.01 Å. There is two shorter (1.95 Å) and two longer (2.00 Å) Fe–F bond length. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO4F2 octahedra. The corner-sharing octahedra tilt angles range from 32–53°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ba2+, one Fe3+, and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Fe3+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Fe3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to three equivalent Ba2+ and one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Ba2+ and two Fe3+ atoms. In the second F1- site, F1- is bonded in a 1-coordinate geometry to two equivalent Ba2+ and one Fe3+ atom.
Ba3Fe2P4(O6F5)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two Ba3Fe2P4(O6F5)2 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 10-coordinate geometry to eight O and two equivalent F atoms. There are a spread of Ba–O bond distances ranging from 2.67–3.14 Å. Both Ba–F bond lengths are 3.34 Å. In the second Ba site, Ba is bonded in a 5-coordinate geometry to two O and three F atoms. There are one shorter (2.49 Å) and one longer (2.72 Å) Ba–O bond lengths. There are a spread of Ba–F bond distances ranging from 2.60–2.89 Å. Fe is bonded to four O and two F atoms to form distorted FeO4F2 octahedra that share corners with four PO3F tetrahedra. There are a spread of Fe–O bond distances ranging from 1.95–2.26 Å. There is one shorter (1.91 Å) and one longer (1.97 Å) Fe–F bond length. There are two inequivalent P sites. In the first P site, P is bonded to two O and two F atoms to form PO2F2 tetrahedra that share corners with two equivalent FeO4F2 octahedra. The corner-sharing octahedra tilt angles range from 39–56°. There is one shorter (1.49 Å) and one longer (1.50 Å) P–O bond length. There is one shorter (1.58 Å) and one longer (1.59 Å) P–F bond length. In the second P site, P is bonded to three O and one F atom to form PO3F tetrahedra that share corners with two equivalent FeO4F2 octahedra. The corner-sharing octahedra tilt angles range from 39–46°. There is one shorter (1.49 Å) and two longer (1.55 Å) P–O bond length. The P–F bond length is 1.59 Å. There are six inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to two equivalent Ba and one P atom. In the second O site, O is bonded in a 3-coordinate geometry to one Ba, one Fe, and one P atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one Ba, one Fe, and one P atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to two Ba atoms. In the fifth O site, O is bonded in a distorted single-bond geometry to one Fe and one P atom. In the sixth O site, O is bonded in a 2-coordinate geometry to one Fe and one P atom. There are five inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one P atom. In the second F site, F is bonded in a bent 120 degrees geometry to one Ba and one Fe atom. In the third F site, F is bonded in a 1-coordinate geometry to two equivalent Ba and one Fe atom. In the fourth F site, F is bonded in a single-bond geometry to one P atom. In the fifth F site, F is bonded in a single-bond geometry to one Ba and one P atom.