Materials Data on Ba2U(AsO5)2 by Materials Project

Ba2U(AsO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.67–3.24 Å. In the second Ba2+ site, Ba2+ is bonded to eight O2- atoms to form distorted BaO8 hexagonal bipyramids that share corners with two UO6 octahedra, corners with four AsO4 tetrahedra, an edgeedge with one BaO8 hexagonal bipyramid, an edgeedge with one UO6 octahedra, and an edgeedge with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–62°. There are a spread of Ba–O bond distances ranging from 2.67–3.20 Å. In the third Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.69–3.09 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.68–3.05 Å. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share a cornercorner with one BaO8 hexagonal bipyramid, corners with four AsO4 tetrahedra, and an edgeedge with one BaO8 hexagonal bipyramid. There are a spread of U–O bond distances ranging from 1.82–2.34 Å. In the second U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share a cornercorner with one BaO8 hexagonal bipyramid and corners with four AsO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.82–2.32 Å. There are four inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two UO6 octahedra and an edgeedge with one BaO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 50–51°. There are a spread of As–O bond distances ranging from 1.69–1.76 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two UO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of As–O bond distances ranging from 1.69–1.76 Å. In the third As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent BaO8 hexagonal bipyramids and corners with two UO6 octahedra. The corner-sharing octahedra tilt angles range from 43–53°. There is two shorter (1.70 Å) and two longer (1.75 Å) As–O bond length. In the fourth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent BaO8 hexagonal bipyramids and corners with two UO6 octahedra. The corner-sharing octahedra tilt angles range from 44–62°. There are a spread of As–O bond distances ranging from 1.70–1.75 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Ba2+, one U6+, and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one U6+, and one As5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, one U6+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, one U6+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ba2+ and one As5+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to two Ba2+ and one U6+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one Ba2+ and one U6+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one U6+, and one As5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+ and one As5+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one U6+, and one As5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one As5+ atom. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one As5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one U6+, and one As5+ atom. In the seventeenth O2- site, O2- is bonded in a single-bond geometry to one Ba2+ and one U6+ atom. In the eighteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ba2+ and one As5+ atom. In the nineteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Ba2+ and one As5+ atom. In the twentieth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one As5+ atom.

Ba₂U(AsO₅)₂晶体属于单斜晶系（monoclinic）P2₁/c空间群（space group），其结构为三维结构（three-dimensional structure）。存在4个不等价的Ba²⁺位点。

第一个Ba²⁺位点中，Ba²⁺以10配位几何（coordinate geometry）结构与10个O²⁻原子成键，Ba–O键长（bond distance）范围为2.67–3.24埃（Å）。

第二个Ba²⁺位点中，Ba²⁺与8个O²⁻原子成键，形成扭曲的BaO₈六方双锥（hexagonal bipyramid）；该双锥与2个UO₆八面体（octahedron）共顶点、与4个AsO₄四面体（tetrahedron）共顶点、与1个BaO₈六方双锥共边、与1个UO₆八面体共边，还与1个AsO₄四面体共边。共顶点八面体的倾斜角（tilt angle）范围为39–62°，Ba–O键长范围为2.67–3.20埃。

第三个Ba²⁺位点中，Ba²⁺以7配位几何结构与7个O²⁻原子成键，Ba–O键长范围为2.69–3.09埃。

第四个Ba²⁺位点中，Ba²⁺以7配位几何结构与7个O²⁻原子成键，Ba–O键长范围为2.68–3.05埃。

存在2个不等价的U⁶⁺位点。第一个U⁶⁺位点中，U⁶⁺与6个O²⁻原子成键形成UO₆八面体；该八面体与1个BaO₈六方双锥共顶点、与4个AsO₄四面体共顶点，还与1个BaO₈六方双锥共边。U–O键长范围为1.82–2.34埃。

第二个U⁶⁺位点中，U⁶⁺与6个O²⁻原子成键形成UO₆八面体；该八面体与1个BaO₈六方双锥共顶点、与4个AsO₄四面体共顶点。U–O键长范围为1.82–2.32埃。

存在4个不等价的As⁵⁺位点。第一个As⁵⁺位点中，As⁵⁺与4个O²⁻原子成键形成AsO₄四面体；该四面体与2个UO₆八面体共顶点，还与1个BaO₈六方双锥共边。共顶点八面体的倾斜角范围为50–51°，As–O键长范围为1.69–1.76埃。

第二个As⁵⁺位点中，As⁵⁺与4个O²⁻原子成键形成AsO₄四面体；该四面体与2个UO₆八面体共顶点。共顶点八面体的倾斜角为48°，As–O键长范围为1.69–1.76埃。

第三个As⁵⁺位点中，As⁵⁺与4个O²⁻原子成键形成AsO₄四面体；该四面体与2个等价的BaO₈六方双锥共顶点、与2个UO₆八面体共顶点。共顶点八面体的倾斜角范围为43–53°，存在2个较短的As–O键（1.70埃）和2个较长的As–O键（1.75埃）。

第四个As⁵⁺位点中，As⁵⁺与4个O²⁻原子成键形成AsO₄四面体；该四面体与2个等价的BaO₈六方双锥共顶点、与2个UO₆八面体共顶点。共顶点八面体的倾斜角范围为44–62°，As–O键长范围为1.70–1.75埃。

存在20个不等价的O²⁻位点。第一个O²⁻位点中，O²⁻以2配位几何结构与2个Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第二个O²⁻位点中，O²⁻以2配位几何结构与2个等价的Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第三个O²⁻位点中，O²⁻以4配位几何结构与2个Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第四个O²⁻位点中，O²⁻以3配位几何结构与2个等价的Ba²⁺和1个As⁵⁺原子成键。

第五个O²⁻位点中，O²⁻以扭曲的单键几何结构与3个Ba²⁺和1个As⁵⁺原子成键。

第六个O²⁻位点中，O²⁻以4配位几何结构与2个等价的Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第七个O²⁻位点中，O²⁻以1配位几何结构与2个等价的Ba²⁺和1个As⁵⁺原子成键。

第八个O²⁻位点中，O²⁻以单键几何结构与2个Ba²⁺和1个U⁶⁺原子成键。

第九个O²⁻位点中，O²⁻以扭曲的单键几何结构与1个Ba²⁺和1个U⁶⁺原子成键。

第十个O²⁻位点中，O²⁻以2配位几何结构与1个Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第十一个O²⁻位点中，O²⁻以3配位几何结构与2个等价的Ba²⁺和1个As⁵⁺原子成键。

第十二个O²⁻位点中，O²⁻以3配位几何结构与1个Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第十三个O²⁻位点中，O²⁻以扭曲的单键几何结构与2个Ba²⁺和1个As⁵⁺原子成键。

第十四个O²⁻位点中，O²⁻以单键几何结构与1个U⁶⁺原子成键。

第十五个O²⁻位点中，O²⁻以扭曲的三角平面（trigonal planar）几何结构与2个等价的Ba²⁺和1个As⁵⁺原子成键。

第十六个O²⁻位点中，O²⁻以3配位几何结构与1个Ba²⁺、1个U⁶⁺和1个As⁵⁺原子成键。

第十七个O²⁻位点中，O²⁻以单键几何结构与1个Ba²⁺和1个U⁶⁺原子成键。

第十八个O²⁻位点中，O²⁻以扭曲的三角平面几何结构与2个Ba²⁺和1个As⁵⁺原子成键。

第十九个O²⁻位点中，O²⁻以1配位几何结构与2个Ba²⁺和1个As⁵⁺原子成键。

第二十个O²⁻位点中，O²⁻以150°扭曲弯曲（bent）几何结构与1个U⁶⁺和1个As⁵⁺原子成键。