MgCd4(TcO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one Cd(2), one O(10), one O(3), one O(6), one O(7), and one O(9) atom. There are four inequivalent Tc sites. In the first Tc site, Tc(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(8) atom to form corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 31-37°. In the second Tc site, Tc(2) is bonded to one O(11), one O(2), one O(3), one O(6), one O(7), and one O(9) atom to form distorted corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 29-42°. In the third Tc site, Tc(3) is bonded to one O(10), one O(12), one O(2), one O(3), one O(6), and one O(7) atom to form distorted corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 29-42°. In the fourth Tc site, Tc(4) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 31-38°. There are four inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(6), one O(7), one O(8), and one O(9) atom. In the second Cd site, Cd(2) is bonded in a 7-coordinate geometry to one Mg(1), one O(1), one O(10), one O(2), one O(5), one O(8), and one O(9) atom. In the third Cd site, Cd(3) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. In the fourth Cd site, Cd(4) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), and one O(6) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Tc(1), one Tc(4), and one Cd(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tc(2), one Tc(3), one Cd(1), and one Cd(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), one Cd(3), and one Cd(4) atom. In the fourth O site, O(4) is bonded to one Tc(1), one Tc(4), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 trigonal pyramids that share  a cornercorner with one O(12)Cd2Tc2 tetrahedra, corners with three equivalent O(11)Cd2Tc2 tetrahedra, corners with three equivalent O(8)Cd3Tc2 trigonal pyramids, and  an edgeedge with one O(12)Cd2Tc2 tetrahedra. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(4), one Cd(2), one Cd(3), and one Cd(4) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), one Cd(1), one Cd(3), and one Cd(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), and one Cd(1) atom. In the eighth O site, O(8) is bonded to one Tc(1), one Tc(4), one Cd(1), one Cd(2), and one Cd(3) atom to form a mixture of distorted edge and corner-sharing OCd3Tc2 trigonal pyramids. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(2), one Tc(4), one Cd(1), and one Cd(2) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(1), one Tc(3), one Cd(1), and one Cd(2) atom. In the eleventh O site, O(11) is bonded to one Tc(2), one Tc(4), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 tetrahedra that share corners with two equivalent O(12)Cd2Tc2 tetrahedra, corners with three equivalent O(4)Cd2Tc2 trigonal pyramids, and  an edgeedge with one O(8)Cd3Tc2 trigonal pyramid. In the twelfth O site, O(12) is bonded to one Tc(1), one Tc(3), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 tetrahedra that share corners with two equivalent O(11)Cd2Tc2 tetrahedra,  a cornercorner with one O(4)Cd2Tc2 trigonal pyramid,  an edgeedge with one O(4)Cd2Tc2 trigonal pyramid, and  an edgeedge with one O(8)Cd3Tc2 trigonal pyramid.
MgCd4(TcO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one Cd(2), one O(10), one O(3), one O(6), one O(7), and one O(9) atom. The Mg(1)-Cd(2) bond length is 2.55 Å. The Mg(1)-O(10) bond length is 2.01 Å. The Mg(1)-O(3) bond length is 2.26 Å. The Mg(1)-O(6) bond length is 2.04 Å. The Mg(1)-O(7) bond length is 1.95 Å. The Mg(1)-O(9) bond length is 2.01 Å. There are four inequivalent Tc sites. In the first Tc site, Tc(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(8) atom to form corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 31-37°. The Tc(1)-O(1) bond length is 2.03 Å. The Tc(1)-O(10) bond length is 2.17 Å. The Tc(1)-O(12) bond length is 2.03 Å. The Tc(1)-O(4) bond length is 2.01 Å. The Tc(1)-O(5) bond length is 2.09 Å. The Tc(1)-O(8) bond length is 2.14 Å. In the second Tc site, Tc(2) is bonded to one O(11), one O(2), one O(3), one O(6), one O(7), and one O(9) atom to form distorted corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 29-42°. The Tc(2)-O(11) bond length is 2.05 Å. The Tc(2)-O(2) bond length is 1.98 Å. The Tc(2)-O(3) bond length is 2.03 Å. The Tc(2)-O(6) bond length is 2.27 Å. The Tc(2)-O(7) bond length is 2.03 Å. The Tc(2)-O(9) bond length is 2.26 Å. In the third Tc site, Tc(3) is bonded to one O(10), one O(12), one O(2), one O(3), one O(6), and one O(7) atom to form distorted corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 29-42°. The Tc(3)-O(10) bond length is 2.33 Å. The Tc(3)-O(12) bond length is 2.02 Å. The Tc(3)-O(2) bond length is 1.99 Å. The Tc(3)-O(3) bond length is 2.05 Å. The Tc(3)-O(6) bond length is 2.14 Å. The Tc(3)-O(7) bond length is 2.14 Å. In the fourth Tc site, Tc(4) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing TcO6 octahedra. The corner-sharing octahedral tilt angles range from 31-38°. The Tc(4)-O(1) bond length is 2.02 Å. The Tc(4)-O(11) bond length is 2.05 Å. The Tc(4)-O(4) bond length is 2.02 Å. The Tc(4)-O(5) bond length is 2.08 Å. The Tc(4)-O(8) bond length is 2.14 Å. The Tc(4)-O(9) bond length is 2.15 Å. There are four inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(6), one O(7), one O(8), and one O(9) atom. The Cd(1)-O(10) bond length is 2.30 Å. The Cd(1)-O(2) bond length is 2.42 Å. The Cd(1)-O(6) bond length is 2.77 Å. The Cd(1)-O(7) bond length is 2.47 Å. The Cd(1)-O(8) bond length is 2.21 Å. The Cd(1)-O(9) bond length is 2.58 Å. In the second Cd site, Cd(2) is bonded in a 7-coordinate geometry to one Mg(1), one O(1), one O(10), one O(2), one O(5), one O(8), and one O(9) atom. The Cd(2)-O(1) bond length is 2.27 Å. The Cd(2)-O(10) bond length is 2.28 Å. The Cd(2)-O(2) bond length is 2.62 Å. The Cd(2)-O(5) bond length is 2.40 Å. The Cd(2)-O(8) bond length is 2.29 Å. The Cd(2)-O(9) bond length is 2.45 Å. In the third Cd site, Cd(3) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. The Cd(3)-O(11) bond length is 2.49 Å. The Cd(3)-O(12) bond length is 2.25 Å. The Cd(3)-O(3) bond length is 2.73 Å. The Cd(3)-O(4) bond length is 2.29 Å. The Cd(3)-O(5) bond length is 2.62 Å. The Cd(3)-O(6) bond length is 2.32 Å. The Cd(3)-O(8) bond length is 2.79 Å. In the fourth Cd site, Cd(4) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), and one O(6) atom. The Cd(4)-O(11) bond length is 2.26 Å. The Cd(4)-O(12) bond length is 2.54 Å. The Cd(4)-O(3) bond length is 2.35 Å. The Cd(4)-O(4) bond length is 2.54 Å. The Cd(4)-O(5) bond length is 2.31 Å. The Cd(4)-O(6) bond length is 2.61 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Tc(1), one Tc(4), and one Cd(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tc(2), one Tc(3), one Cd(1), and one Cd(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), one Cd(3), and one Cd(4) atom. In the fourth O site, O(4) is bonded to one Tc(1), one Tc(4), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 trigonal pyramids that share  a cornercorner with one O(12)Cd2Tc2 tetrahedra, corners with three equivalent O(11)Cd2Tc2 tetrahedra, corners with three equivalent O(8)Cd3Tc2 trigonal pyramids, and  an edgeedge with one O(12)Cd2Tc2 tetrahedra. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Tc(1), one Tc(4), one Cd(2), one Cd(3), and one Cd(4) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), one Cd(1), one Cd(3), and one Cd(4) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Mg(1), one Tc(2), one Tc(3), and one Cd(1) atom. In the eighth O site, O(8) is bonded to one Tc(1), one Tc(4), one Cd(1), one Cd(2), and one Cd(3) atom to form a mixture of distorted edge and corner-sharing OCd3Tc2 trigonal pyramids. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(2), one Tc(4), one Cd(1), and one Cd(2) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Mg(1), one Tc(1), one Tc(3), one Cd(1), and one Cd(2) atom. In the eleventh O site, O(11) is bonded to one Tc(2), one Tc(4), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 tetrahedra that share corners with two equivalent O(12)Cd2Tc2 tetrahedra, corners with three equivalent O(4)Cd2Tc2 trigonal pyramids, and  an edgeedge with one O(8)Cd3Tc2 trigonal pyramid. In the twelfth O site, O(12) is bonded to one Tc(1), one Tc(3), one Cd(3), and one Cd(4) atom to form distorted OCd2Tc2 tetrahedra that share corners with two equivalent O(11)Cd2Tc2 tetrahedra,  a cornercorner with one O(4)Cd2Tc2 trigonal pyramid,  an edgeedge with one O(4)Cd2Tc2 trigonal pyramid, and  an edgeedge with one O(8)Cd3Tc2 trigonal pyramid.