MgCo4(P2O7)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(12), one O(13), one O(5), one O(6), and one O(7) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(14), one O(17), one O(2), one O(25), one O(26), and one O(3) atom to form CoO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), one O(18), one O(24), one O(27), one O(28), and one O(4) atom to form CoO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the third Co site, Co(3) is bonded to one O(10), one O(16), one O(19), one O(7), and one O(9) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. In the fourth Co site, Co(4) is bonded to one O(11), one O(12), one O(20), one O(23), and one O(6) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, and  a cornercorner with one P(6)O4 tetrahedra. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(13), one O(14), and one O(22) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 41°. In the second P site, P(2) is bonded to one O(15), one O(23), one O(24), and one O(25) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 50-56°. In the third P site, P(3) is bonded to one O(1), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(8)O4 tetrahedra,  a cornercorner with one Co(3)O5 trigonal bipyramid, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 49°. In the fourth P site, P(4) is bonded to one O(18), one O(22), one O(26), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 47-48°. In the fifth P site, P(5) is bonded to one O(27), one O(5), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 43°. In the sixth P site, P(6) is bonded to one O(11), one O(15), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Co(3)O5 trigonal bipyramid, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 42°. In the seventh P site, P(7) is bonded to one O(16), one O(17), one O(28), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-50°. In the eighth P site, P(8) is bonded to one O(10), one O(2), one O(21), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-48°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Co(2) and one P(3) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Co(1) and one P(8) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Co(1) and one P(6) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(8) atom. In the fifth O site, O(5) is bonded in an L-shaped geometry to one Mg(1) and one P(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(4), and one P(4) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(3), and one P(5) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(5) and one P(7) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Co(3) and one P(6) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Co(3) and one P(8) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Co(4) and one P(6) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Mg(1), one Co(4), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a water-like geometry to one Mg(1) and one P(1) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Co(1) and one P(1) atom. In the fifteenth O site, O(15) is bonded in a bent 120 degrees geometry to one P(2) and one P(6) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Co(3) and one P(7) atom. In the seventeenth O site, O(17) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one P(7) atom. In the eighteenth O site, O(18) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(4) atom. In the nineteenth O site, O(19) is bonded in a bent 120 degrees geometry to one Co(3) and one P(3) atom. In the twentieth O site, O(20) is bonded in a bent 120 degrees geometry to one Co(4) and one P(3) atom. In the twenty-first O site, O(21) is bonded in a bent 120 degrees geometry to one P(3) and one P(8) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one P(1) and one P(4) atom. In the twenty-third O site, O(23) is bonded in a bent 120 degrees geometry to one Co(4) and one P(2) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one Co(2) and one P(2) atom. In the twenty-fifth O site, O(25) is bonded in a bent 120 degrees geometry to one Co(1) and one P(2) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 120 degrees geometry to one Co(1) and one P(4) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one Co(2) and one P(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(7) atom.
MgCo4(P2O7)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(12), one O(13), one O(5), one O(6), and one O(7) atom. The Mg(1)-O(12) bond length is 2.29 Å. The Mg(1)-O(13) bond length is 1.99 Å. The Mg(1)-O(5) bond length is 2.10 Å. The Mg(1)-O(6) bond length is 1.99 Å. The Mg(1)-O(7) bond length is 2.03 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(14), one O(17), one O(2), one O(25), one O(26), and one O(3) atom to form CoO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. The Co(1)-O(14) bond length is 1.95 Å. The Co(1)-O(17) bond length is 1.94 Å. The Co(1)-O(2) bond length is 2.02 Å. The Co(1)-O(25) bond length is 2.08 Å. The Co(1)-O(26) bond length is 2.11 Å. The Co(1)-O(3) bond length is 1.94 Å. In the second Co site, Co(2) is bonded to one O(1), one O(18), one O(24), one O(27), one O(28), and one O(4) atom to form CoO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. The Co(2)-O(1) bond length is 1.89 Å. The Co(2)-O(18) bond length is 1.94 Å. The Co(2)-O(24) bond length is 1.92 Å. The Co(2)-O(27) bond length is 1.93 Å. The Co(2)-O(28) bond length is 2.00 Å. The Co(2)-O(4) bond length is 1.94 Å. In the third Co site, Co(3) is bonded to one O(10), one O(16), one O(19), one O(7), and one O(9) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one P(8)O4 tetrahedra. The Co(3)-O(10) bond length is 1.91 Å. The Co(3)-O(16) bond length is 1.91 Å. The Co(3)-O(19) bond length is 1.95 Å. The Co(3)-O(7) bond length is 2.02 Å. The Co(3)-O(9) bond length is 1.90 Å. In the fourth Co site, Co(4) is bonded to one O(11), one O(12), one O(20), one O(23), and one O(6) atom to form CoO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, and  a cornercorner with one P(6)O4 tetrahedra. The Co(4)-O(11) bond length is 1.92 Å. The Co(4)-O(12) bond length is 2.03 Å. The Co(4)-O(20) bond length is 1.87 Å. The Co(4)-O(23) bond length is 1.91 Å. The Co(4)-O(6) bond length is 2.01 Å. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(13), one O(14), and one O(22) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 41°. The P(1)-O(12) bond length is 1.57 Å. The P(1)-O(13) bond length is 1.52 Å. The P(1)-O(14) bond length is 1.53 Å. The P(1)-O(22) bond length is 1.60 Å. In the second P site, P(2) is bonded to one O(15), one O(23), one O(24), and one O(25) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 50-56°. The P(2)-O(15) bond length is 1.63 Å. The P(2)-O(23) bond length is 1.55 Å. The P(2)-O(24) bond length is 1.55 Å. The P(2)-O(25) bond length is 1.52 Å. In the third P site, P(3) is bonded to one O(1), one O(19), one O(20), and one O(21) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(8)O4 tetrahedra,  a cornercorner with one Co(3)O5 trigonal bipyramid, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 49°. The P(3)-O(1) bond length is 1.54 Å. The P(3)-O(19) bond length is 1.53 Å. The P(3)-O(20) bond length is 1.54 Å. The P(3)-O(21) bond length is 1.60 Å. In the fourth P site, P(4) is bonded to one O(18), one O(22), one O(26), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 47-48°. The P(4)-O(18) bond length is 1.54 Å. The P(4)-O(22) bond length is 1.63 Å. The P(4)-O(26) bond length is 1.50 Å. The P(4)-O(6) bond length is 1.57 Å. In the fifth P site, P(5) is bonded to one O(27), one O(5), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(7)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 43°. The P(5)-O(27) bond length is 1.53 Å. The P(5)-O(5) bond length is 1.52 Å. The P(5)-O(7) bond length is 1.58 Å. The P(5)-O(8) bond length is 1.62 Å. In the sixth P site, P(6) is bonded to one O(11), one O(15), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one Co(3)O5 trigonal bipyramid, and  a cornercorner with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 42°. The P(6)-O(11) bond length is 1.53 Å. The P(6)-O(15) bond length is 1.62 Å. The P(6)-O(3) bond length is 1.52 Å. The P(6)-O(9) bond length is 1.55 Å. In the seventh P site, P(7) is bonded to one O(16), one O(17), one O(28), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(5)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-50°. The P(7)-O(16) bond length is 1.55 Å. The P(7)-O(17) bond length is 1.53 Å. The P(7)-O(28) bond length is 1.54 Å. The P(7)-O(8) bond length is 1.64 Å. In the eighth P site, P(8) is bonded to one O(10), one O(2), one O(21), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one Co(3)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-48°. The P(8)-O(10) bond length is 1.54 Å. The P(8)-O(2) bond length is 1.52 Å. The P(8)-O(21) bond length is 1.62 Å. The P(8)-O(4) bond length is 1.56 Å. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Co(2) and one P(3) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Co(1) and one P(8) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Co(1) and one P(6) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(8) atom. In the fifth O site, O(5) is bonded in an L-shaped geometry to one Mg(1) and one P(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(4), and one P(4) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(3), and one P(5) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(5) and one P(7) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Co(3) and one P(6) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Co(3) and one P(8) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Co(4) and one P(6) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Mg(1), one Co(4), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a water-like geometry to one Mg(1) and one P(1) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Co(1) and one P(1) atom. In the fifteenth O site, O(15) is bonded in a bent 120 degrees geometry to one P(2) and one P(6) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Co(3) and one P(7) atom. In the seventeenth O site, O(17) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one P(7) atom. In the eighteenth O site, O(18) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(4) atom. In the nineteenth O site, O(19) is bonded in a bent 120 degrees geometry to one Co(3) and one P(3) atom. In the twentieth O site, O(20) is bonded in a bent 120 degrees geometry to one Co(4) and one P(3) atom. In the twenty-first O site, O(21) is bonded in a bent 120 degrees geometry to one P(3) and one P(8) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one P(1) and one P(4) atom. In the twenty-third O site, O(23) is bonded in a bent 120 degrees geometry to one Co(4) and one P(2) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one Co(2) and one P(2) atom. In the twenty-fifth O site, O(25) is bonded in a bent 120 degrees geometry to one Co(1) and one P(2) atom. In the twenty-sixth O site, O(26) is bonded in a distorted bent 120 degrees geometry to one Co(1) and one P(4) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one Co(2) and one P(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted bent 120 degrees geometry to one Co(2) and one P(7) atom.