Ca4Mg3Fe(SiO3)8 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(13), one O(15), one O(18), one O(19), one O(3), one O(5), and one O(7) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(14), one O(16), one O(17), one O(2), one O(20), one O(4), one O(6), and one O(8) atom. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(22), one O(23), one O(3), one O(5), one O(7), and one O(9) atom. In the fourth Ca site, Ca(4) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(2), one O(21), one O(24), one O(4), one O(6), and one O(8) atom. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(10), one O(12), one O(18), one O(19), one O(21), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(2)O6 octahedra. In the second Mg site, Mg(2) is bonded to one O(13), one O(15), one O(18), one O(19), one O(21), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(5)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(14), one O(16), one O(17), one O(20), one O(22), and one O(23) atom to form MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(6)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. Fe(1) is bonded to one O(11), one O(17), one O(20), one O(22), one O(23), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and edges with two equivalent Mg(3)O6 octahedra. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(17), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. In the second Si site, Si(2) is bonded to one O(10), one O(18), one O(2), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. In the third Si site, Si(3) is bonded to one O(11), one O(19), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-58°. In the fourth Si site, Si(4) is bonded to one O(12), one O(20), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-59°. In the fifth Si site, Si(5) is bonded to one O(13), one O(21), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. In the sixth Si site, Si(6) is bonded to one O(14), one O(22), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-60°. In the seventh Si site, Si(7) is bonded to one O(1), one O(15), one O(23), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-60°. In the eighth Si site, Si(8) is bonded to one O(16), one O(2), one O(24), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(1), and one Si(7) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(2), and one Si(8) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(3), and one Si(5) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(4), and one Si(6) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(3), and one Si(5) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(4), and one Si(6) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(1), and one Si(7) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(2), and one Si(8) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Ca(3), one Fe(1), and one Si(1) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Ca(4), one Mg(1), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to one Ca(3), one Fe(1), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Ca(4), one Mg(1), and one Si(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(2), and one Si(5) atom. In the fourteenth O site, O(14) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(3), and one Si(6) atom. In the fifteenth O site, O(15) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(2), and one Si(7) atom. In the sixteenth O site, O(16) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(3), and one Si(8) atom. In the seventeenth O site, O(17) is bonded in a 4-coordinate geometry to one Ca(2), one Mg(3), one Fe(1), and one Si(1) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), and one Si(2) atom. In the nineteenth O site, O(19) is bonded in a 4-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), and one Si(3) atom. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Ca(2), one Mg(3), one Fe(1), and one Si(4) atom. In the twenty-first O site, O(21) is bonded in a 4-coordinate geometry to one Ca(4), one Mg(1), one Mg(2), and one Si(5) atom. In the twenty-second O site, O(22) is bonded to one Ca(3), one Mg(3), one Fe(1), and one Si(6) atom to form a mixture of distorted corner and edge-sharing OCaMgFeSi trigonal pyramids. In the twenty-third O site, O(23) is bonded to one Ca(3), one Mg(3), one Fe(1), and one Si(7) atom to form a mixture of distorted corner and edge-sharing OCaMgFeSi trigonal pyramids. In the twenty-fourth O site, O(24) is bonded in a 4-coordinate geometry to one Ca(4), one Mg(1), one Mg(2), and one Si(8) atom.
Ca4Mg3Fe(SiO3)8 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(13), one O(15), one O(18), one O(19), one O(3), one O(5), and one O(7) atom. The Ca(1)-O(1) bond length is 2.61 Å. The Ca(1)-O(13) bond length is 2.35 Å. The Ca(1)-O(15) bond length is 2.35 Å. The Ca(1)-O(18) bond length is 2.38 Å. The Ca(1)-O(19) bond length is 2.39 Å. The Ca(1)-O(3) bond length is 2.61 Å. The Ca(1)-O(5) bond length is 2.79 Å. The Ca(1)-O(7) bond length is 2.79 Å. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(14), one O(16), one O(17), one O(2), one O(20), one O(4), one O(6), and one O(8) atom. The Ca(2)-O(14) bond length is 2.35 Å. The Ca(2)-O(16) bond length is 2.35 Å. The Ca(2)-O(17) bond length is 2.37 Å. The Ca(2)-O(2) bond length is 2.60 Å. The Ca(2)-O(20) bond length is 2.37 Å. The Ca(2)-O(4) bond length is 2.60 Å. The Ca(2)-O(6) bond length is 2.79 Å. The Ca(2)-O(8) bond length is 2.79 Å. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(22), one O(23), one O(3), one O(5), one O(7), and one O(9) atom. The Ca(3)-O(1) bond length is 2.80 Å. The Ca(3)-O(11) bond length is 2.35 Å. The Ca(3)-O(22) bond length is 2.37 Å. The Ca(3)-O(23) bond length is 2.37 Å. The Ca(3)-O(3) bond length is 2.80 Å. The Ca(3)-O(5) bond length is 2.63 Å. The Ca(3)-O(7) bond length is 2.63 Å. The Ca(3)-O(9) bond length is 2.35 Å. In the fourth Ca site, Ca(4) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(2), one O(21), one O(24), one O(4), one O(6), and one O(8) atom. The Ca(4)-O(10) bond length is 2.35 Å. The Ca(4)-O(12) bond length is 2.35 Å. The Ca(4)-O(2) bond length is 2.79 Å. The Ca(4)-O(21) bond length is 2.39 Å. The Ca(4)-O(24) bond length is 2.39 Å. The Ca(4)-O(4) bond length is 2.79 Å. The Ca(4)-O(6) bond length is 2.61 Å. The Ca(4)-O(8) bond length is 2.61 Å. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(10), one O(12), one O(18), one O(19), one O(21), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Mg(2)O6 octahedra. The Mg(1)-O(10) bond length is 2.08 Å. The Mg(1)-O(12) bond length is 2.08 Å. The Mg(1)-O(18) bond length is 2.16 Å. The Mg(1)-O(19) bond length is 2.16 Å. The Mg(1)-O(21) bond length is 2.09 Å. The Mg(1)-O(24) bond length is 2.09 Å. In the second Mg site, Mg(2) is bonded to one O(13), one O(15), one O(18), one O(19), one O(21), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(5)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. The Mg(2)-O(13) bond length is 2.08 Å. The Mg(2)-O(15) bond length is 2.08 Å. The Mg(2)-O(18) bond length is 2.09 Å. The Mg(2)-O(19) bond length is 2.09 Å. The Mg(2)-O(21) bond length is 2.16 Å. The Mg(2)-O(24) bond length is 2.16 Å. In the third Mg site, Mg(3) is bonded to one O(14), one O(16), one O(17), one O(20), one O(22), and one O(23) atom to form MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  a cornercorner with one Si(8)O4 tetrahedra, corners with two equivalent Si(6)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. The Mg(3)-O(14) bond length is 2.08 Å. The Mg(3)-O(16) bond length is 2.09 Å. The Mg(3)-O(17) bond length is 2.08 Å. The Mg(3)-O(20) bond length is 2.08 Å. The Mg(3)-O(22) bond length is 2.15 Å. The Mg(3)-O(23) bond length is 2.15 Å. Fe(1) is bonded to one O(11), one O(17), one O(20), one O(22), one O(23), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and edges with two equivalent Mg(3)O6 octahedra. The Fe(1)-O(11) bond length is 2.11 Å. The Fe(1)-O(17) bond length is 2.19 Å. The Fe(1)-O(20) bond length is 2.20 Å. The Fe(1)-O(22) bond length is 2.14 Å. The Fe(1)-O(23) bond length is 2.14 Å. The Fe(1)-O(9) bond length is 2.10 Å. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(17), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. The Si(1)-O(1) bond length is 1.68 Å. The Si(1)-O(17) bond length is 1.62 Å. The Si(1)-O(7) bond length is 1.70 Å. The Si(1)-O(9) bond length is 1.60 Å. In the second Si site, Si(2) is bonded to one O(10), one O(18), one O(2), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Si(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. The Si(2)-O(10) bond length is 1.61 Å. The Si(2)-O(18) bond length is 1.62 Å. The Si(2)-O(2) bond length is 1.69 Å. The Si(2)-O(8) bond length is 1.71 Å. In the third Si site, Si(3) is bonded to one O(11), one O(19), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-58°. The Si(3)-O(11) bond length is 1.60 Å. The Si(3)-O(19) bond length is 1.62 Å. The Si(3)-O(3) bond length is 1.68 Å. The Si(3)-O(5) bond length is 1.70 Å. In the fourth Si site, Si(4) is bonded to one O(12), one O(20), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-59°. The Si(4)-O(12) bond length is 1.60 Å. The Si(4)-O(20) bond length is 1.62 Å. The Si(4)-O(4) bond length is 1.69 Å. The Si(4)-O(6) bond length is 1.71 Å. In the fifth Si site, Si(5) is bonded to one O(13), one O(21), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. The Si(5)-O(13) bond length is 1.61 Å. The Si(5)-O(21) bond length is 1.62 Å. The Si(5)-O(3) bond length is 1.71 Å. The Si(5)-O(5) bond length is 1.69 Å. In the sixth Si site, Si(6) is bonded to one O(14), one O(22), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-60°. The Si(6)-O(14) bond length is 1.60 Å. The Si(6)-O(22) bond length is 1.62 Å. The Si(6)-O(4) bond length is 1.70 Å. The Si(6)-O(6) bond length is 1.69 Å. In the seventh Si site, Si(7) is bonded to one O(1), one O(15), one O(23), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-60°. The Si(7)-O(1) bond length is 1.70 Å. The Si(7)-O(15) bond length is 1.60 Å. The Si(7)-O(23) bond length is 1.62 Å. The Si(7)-O(7) bond length is 1.68 Å. In the eighth Si site, Si(8) is bonded to one O(16), one O(2), one O(24), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(3)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-58°. The Si(8)-O(16) bond length is 1.61 Å. The Si(8)-O(2) bond length is 1.71 Å. The Si(8)-O(24) bond length is 1.62 Å. The Si(8)-O(8) bond length is 1.69 Å. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(1), and one Si(7) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(2), and one Si(8) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(3), and one Si(5) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(4), and one Si(6) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(3), and one Si(5) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(4), and one Si(6) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ca(1), one Ca(3), one Si(1), and one Si(7) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(4), one Si(2), and one Si(8) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Ca(3), one Fe(1), and one Si(1) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Ca(4), one Mg(1), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to one Ca(3), one Fe(1), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Ca(4), one Mg(1), and one Si(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(2), and one Si(5) atom. In the fourteenth O site, O(14) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(3), and one Si(6) atom. In the fifteenth O site, O(15) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(2), and one Si(7) atom. In the sixteenth O site, O(16) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(3), and one Si(8) atom. In the seventeenth O site, O(17) is bonded in a 4-coordinate geometry to one Ca(2), one Mg(3), one Fe(1), and one Si(1) atom. In the eighteenth O site, O(18) is bonded in a 4-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), and one Si(2) atom. In the nineteenth O site, O(19) is bonded in a 4-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), and one Si(3) atom. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Ca(2), one Mg(3), one Fe(1), and one Si(4) atom. In the twenty-first O site, O(21) is bonded in a 4-coordinate geometry to one Ca(4), one Mg(1), one Mg(2), and one Si(5) atom. In the twenty-second O site, O(22) is bonded to one Ca(3), one Mg(3), one Fe(1), and one Si(6) atom to form a mixture of distorted corner and edge-sharing OCaMgFeSi trigonal pyramids. In the twenty-third O site, O(23) is bonded to one Ca(3), one Mg(3), one Fe(1), and one Si(7) atom to form a mixture of distorted corner and edge-sharing OCaMgFeSi trigonal pyramids. In the twenty-fourth O site, O(24) is bonded in a 4-coordinate geometry to one Ca(4), one Mg(1), one Mg(2), and one Si(8) atom.