NaCa3MgFe(Si2O7)2 crystallizes in the triclinic P1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(2), one O(4), one O(5), one O(6), and one O(9) atom. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(2), one O(3), one O(5), and one O(6) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(13), one O(2), one O(3), one O(4), one O(7), 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(12), one O(14), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. Mg(1) is bonded to one O(11), one O(5), one O(7), and one O(9) atom to form MgO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. Fe(1) is bonded to one O(10), one O(12), one O(6), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(12), one O(14), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(11), one O(13), one O(2), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(10), one O(14), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(1)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(13), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Ca(1), one Ca(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing ONaCa2Si tetrahedra. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Na(1), one Ca(1), one Ca(2), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Na(1), one Ca(2), one Ca(3), and one Si(4) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Mg(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Mg(1), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Fe(1), and one Si(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Na(1), one Ca(3), one Mg(1), and one Si(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Fe(1), and one Si(3) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mg(1), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(1), one Ca(3), one Fe(1), and one Si(1) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Na(1), one Ca(2), one Si(2), and one Si(4) atom. In the fourteenth O site, O(14) is bonded to one Ca(1), one Ca(3), one Si(1), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OCa2Si2 tetrahedra.
NaCa3MgFe(Si2O7)2 crystallizes in the triclinic P1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(13), one O(2), one O(4), one O(5), one O(6), and one O(9) atom. The Na(1)-O(1) bond length is 2.63 Å. The Na(1)-O(12) bond length is 2.54 Å. The Na(1)-O(13) bond length is 2.50 Å. The Na(1)-O(2) bond length is 2.98 Å. The Na(1)-O(4) bond length is 2.96 Å. The Na(1)-O(5) bond length is 2.44 Å. The Na(1)-O(6) bond length is 2.90 Å. The Na(1)-O(9) bond length is 2.87 Å. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(2), one O(3), one O(5), and one O(6) atom. The Ca(1)-O(1) bond length is 2.53 Å. The Ca(1)-O(10) bond length is 2.86 Å. The Ca(1)-O(11) bond length is 2.36 Å. The Ca(1)-O(14) bond length is 2.46 Å. The Ca(1)-O(2) bond length is 2.44 Å. The Ca(1)-O(3) bond length is 2.91 Å. The Ca(1)-O(5) bond length is 2.58 Å. The Ca(1)-O(6) bond length is 2.54 Å. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(13), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. The Ca(2)-O(10) bond length is 2.55 Å. The Ca(2)-O(11) bond length is 2.62 Å. The Ca(2)-O(13) bond length is 2.53 Å. The Ca(2)-O(2) bond length is 2.56 Å. The Ca(2)-O(3) bond length is 2.51 Å. The Ca(2)-O(4) bond length is 2.60 Å. The Ca(2)-O(7) bond length is 2.40 Å. The Ca(2)-O(8) bond length is 2.72 Å. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(14), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. The Ca(3)-O(1) bond length is 2.59 Å. The Ca(3)-O(12) bond length is 2.78 Å. The Ca(3)-O(14) bond length is 2.44 Å. The Ca(3)-O(3) bond length is 2.77 Å. The Ca(3)-O(4) bond length is 2.45 Å. The Ca(3)-O(7) bond length is 2.74 Å. The Ca(3)-O(8) bond length is 2.49 Å. The Ca(3)-O(9) bond length is 2.36 Å. Mg(1) is bonded to one O(11), one O(5), one O(7), and one O(9) atom to form MgO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The Mg(1)-O(11) bond length is 1.96 Å. The Mg(1)-O(5) bond length is 1.94 Å. The Mg(1)-O(7) bond length is 1.95 Å. The Mg(1)-O(9) bond length is 1.95 Å. Fe(1) is bonded to one O(10), one O(12), one O(6), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The Fe(1)-O(10) bond length is 1.89 Å. The Fe(1)-O(12) bond length is 1.88 Å. The Fe(1)-O(6) bond length is 1.89 Å. The Fe(1)-O(8) bond length is 1.90 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(12), one O(14), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The Si(1)-O(1) bond length is 1.62 Å. The Si(1)-O(12) bond length is 1.66 Å. The Si(1)-O(14) bond length is 1.69 Å. The Si(1)-O(5) bond length is 1.62 Å. In the second Si site, Si(2) is bonded to one O(11), one O(13), one O(2), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The Si(2)-O(11) bond length is 1.64 Å. The Si(2)-O(13) bond length is 1.68 Å. The Si(2)-O(2) bond length is 1.61 Å. The Si(2)-O(6) bond length is 1.66 Å. In the third Si site, Si(3) is bonded to one O(10), one O(14), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(1)O4 tetrahedra. The Si(3)-O(10) bond length is 1.66 Å. The Si(3)-O(14) bond length is 1.68 Å. The Si(3)-O(3) bond length is 1.61 Å. The Si(3)-O(7) bond length is 1.63 Å. In the fourth Si site, Si(4) is bonded to one O(13), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. The Si(4)-O(13) bond length is 1.68 Å. The Si(4)-O(4) bond length is 1.61 Å. The Si(4)-O(8) bond length is 1.68 Å. The Si(4)-O(9) bond length is 1.63 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Ca(1), one Ca(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing ONaCa2Si tetrahedra. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Na(1), one Ca(1), one Ca(2), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Na(1), one Ca(2), one Ca(3), and one Si(4) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Mg(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Mg(1), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Fe(1), and one Si(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Na(1), one Ca(3), one Mg(1), and one Si(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Fe(1), and one Si(3) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mg(1), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(1), one Ca(3), one Fe(1), and one Si(1) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Na(1), one Ca(2), one Si(2), and one Si(4) atom. In the fourteenth O site, O(14) is bonded to one Ca(1), one Ca(3), one Si(1), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OCa2Si2 tetrahedra.