Ba3P2(SeO)4 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one Se(1), one O(1), one O(4), and two equivalent O(2) atoms. In the third Ba site, Ba(3) is bonded in a 1-coordinate geometry to three equivalent Se(1) and one O(4) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second P site, P(2) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ba(2), three equivalent Ba(3), and one P(2) atom to form a mixture of distorted edge and corner-sharing SeBa4P square pyramids. In the second Se site, Se(2) is bonded in a distorted single-bond geometry to one P(2) atom. In the third Se site, Se(3) is bonded in a distorted single-bond geometry to one P(2) atom. In the fourth Se site, Se(4) is bonded in a 1-coordinate geometry to one P(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one P(1) atom.
Ba3P2(SeO)4 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(3) atoms. The Ba(1)-O(1) bond length is 2.88 Å. The Ba(1)-O(2) bond length is 2.79 Å. The Ba(1)-O(4) bond length is 2.85 Å. There is one shorter (2.70 Å) and one longer (2.89 Å) Ba(1)-O(3) bond length. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one Se(1), one O(1), one O(4), and two equivalent O(2) atoms. The Ba(2)-Se(1) bond length is 3.36 Å. The Ba(2)-O(1) bond length is 2.73 Å. The Ba(2)-O(4) bond length is 2.93 Å. There is one shorter (2.72 Å) and one longer (2.80 Å) Ba(2)-O(2) bond length. In the third Ba site, Ba(3) is bonded in a 1-coordinate geometry to three equivalent Se(1) and one O(4) atom. There are a spread of Ba(3)-Se(1) bond distances ranging from 3.45-3.71 Å. The Ba(3)-O(4) bond length is 2.65 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The P(1)-O(1) bond length is 1.56 Å. The P(1)-O(2) bond length is 1.57 Å. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.57 Å. In the second P site, P(2) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. The P(2)-Se(1) bond length is 2.23 Å. The P(2)-Se(2) bond length is 2.22 Å. The P(2)-Se(3) bond length is 2.21 Å. The P(2)-Se(4) bond length is 2.22 Å. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Ba(2), three equivalent Ba(3), and one P(2) atom to form a mixture of distorted edge and corner-sharing SeBa4P square pyramids. In the second Se site, Se(2) is bonded in a distorted single-bond geometry to one P(2) atom. In the third Se site, Se(3) is bonded in a distorted single-bond geometry to one P(2) atom. In the fourth Se site, Se(4) is bonded in a 1-coordinate geometry to one P(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one P(1) atom.