BaC3P3NH10O9 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(7), two equivalent O(4), and two equivalent O(9) atoms. The Ba(1)-O(1) bond length is 2.89 Å. The Ba(1)-O(2) bond length is 2.74 Å. The Ba(1)-O(5) bond length is 2.80 Å. The Ba(1)-O(6) bond length is 2.97 Å. The Ba(1)-O(7) bond length is 2.87 Å. There is one shorter (2.68 Å) and one longer (3.03 Å) Ba(1)-O(4) bond length. There is one shorter (2.74 Å) and one longer (2.94 Å) Ba(1)-O(9) bond length. There are three inequivalent C sites. In the first C site, C(1) is bonded to one P(1), one N(1), one H(1), and one H(2) atom to form distorted corner-sharing CPH2N tetrahedra. The C(1)-P(1) bond length is 1.84 Å. The C(1)-N(1) bond length is 1.51 Å. The C(1)-H(1) bond length is 1.10 Å. The C(1)-H(2) bond length is 1.10 Å. In the second C site, C(2) is bonded to one P(2), one N(1), one H(3), and one H(4) atom to form distorted corner-sharing CPH2N tetrahedra. The C(2)-P(2) bond length is 1.83 Å. The C(2)-N(1) bond length is 1.51 Å. The C(2)-H(3) bond length is 1.10 Å. The C(2)-H(4) bond length is 1.10 Å. In the third C site, C(3) is bonded to one P(3), one N(1), one H(5), and one H(6) atom to form distorted corner-sharing CPH2N tetrahedra. The C(3)-P(3) bond length is 1.84 Å. The C(3)-N(1) bond length is 1.51 Å. The C(3)-H(5) bond length is 1.10 Å. The C(3)-H(6) bond length is 1.10 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one C(1), one O(1), one O(2), and one O(3) atom to form distorted PCO3 tetrahedra that share  a cornercorner with one N(1)HC3 tetrahedra. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.50 Å. The P(1)-O(3) bond length is 1.59 Å. In the second P site, P(2) is bonded to one C(2), one O(4), one O(5), and one O(6) atom to form PCO3 tetrahedra that share  a cornercorner with one N(1)HC3 tetrahedra. The P(2)-O(4) bond length is 1.51 Å. The P(2)-O(5) bond length is 1.53 Å. The P(2)-O(6) bond length is 1.58 Å. In the third P site, P(3) is bonded to one C(3), one O(7), one O(8), and one O(9) atom to form distorted PCO3 tetrahedra that share  a cornercorner with one N(1)HC3 tetrahedra. The P(3)-O(7) bond length is 1.53 Å. The P(3)-O(8) bond length is 1.58 Å. The P(3)-O(9) bond length is 1.51 Å. N(1) is bonded to one C(1), one C(2), one C(3), and one H(7) atom to form distorted NHC3 tetrahedra that share  a cornercorner with one P(1)CO3 tetrahedra,  a cornercorner with one P(2)CO3 tetrahedra, and  a cornercorner with one P(3)CO3 tetrahedra. The N(1)-H(7) bond length is 1.04 Å. There are ten inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(1) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(2) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(2) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(3) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(3) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one N(1) atom. In the eighth H site, H(8) is bonded in a linear geometry to one O(3) and one O(5) atom. The H(8)-O(3) bond length is 1.03 Å. The H(8)-O(5) bond length is 1.57 Å. In the ninth H site, H(9) is bonded in a linear geometry to one O(1) and one O(6) atom. The H(9)-O(1) bond length is 1.41 Å. The H(9)-O(6) bond length is 1.07 Å. In the tenth H site, H(10) is bonded in a linear geometry to one O(7) and one O(8) atom. The H(10)-O(7) bond length is 1.47 Å. The H(10)-O(8) bond length is 1.04 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(1), and one H(9) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one H(8) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(2), and one H(8) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(2), and one H(9) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one P(3), and one H(10) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(3) and one H(10) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one P(3) atom. Linkers: 1 [O]P(=O)(C[NH](CP(=O)([O])O)CP(=O)([O])O)O ,1 [O]P(=O)(C[NH](CP(=O)(O)[O])CP(=O)(O)[O])O. Metal clusters: 2 [Ba]. The MOF has largest included sphere 1.81 A, density 2.65 g/cm3, surface area 2429.29 m2/g, accessible volume 0.04 cm3/g