ErMoO4Br crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), one Br(2), and two equivalent Br(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), one O(8), and one Br(2) atom. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second Mo site, Mo(2) is bonded in a tetrahedral geometry to one O(5), one O(6), one O(7), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Er(2) and one Mo(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Er(1) and one Mo(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Er(1), one Er(2), and one Mo(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Er(1), one Er(2), and one Mo(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Er(2) and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to one Er(1) and one Mo(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Er(2) and one Mo(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Er(1), one Er(2), and one Mo(2) atom. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a water-like geometry to two equivalent Er(1) atoms. In the second Br site, Br(2) is bonded in a distorted bent 120 degrees geometry to one Er(1) and one Er(2) atom.
ErMoO4Br crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), one Br(2), and two equivalent Br(1) atoms. The Er(1)-O(2) bond length is 2.27 Å. The Er(1)-O(3) bond length is 2.87 Å. The Er(1)-O(4) bond length is 2.46 Å. The Er(1)-O(6) bond length is 2.27 Å. The Er(1)-O(8) bond length is 2.29 Å. The Er(1)-Br(2) bond length is 2.90 Å. There is one shorter (2.88 Å) and one longer (2.90 Å) Er(1)-Br(1) bond length. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), one O(8), and one Br(2) atom. The Er(2)-O(1) bond length is 2.27 Å. The Er(2)-O(3) bond length is 2.27 Å. The Er(2)-O(4) bond length is 2.27 Å. The Er(2)-O(5) bond length is 2.28 Å. The Er(2)-O(7) bond length is 2.28 Å. The Er(2)-O(8) bond length is 2.41 Å. The Er(2)-Br(2) bond length is 2.98 Å. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Mo(1)-O(1) bond length is 1.77 Å. The Mo(1)-O(2) bond length is 1.78 Å. The Mo(1)-O(3) bond length is 1.81 Å. The Mo(1)-O(4) bond length is 1.84 Å. In the second Mo site, Mo(2) is bonded in a tetrahedral geometry to one O(5), one O(6), one O(7), and one O(8) atom. The Mo(2)-O(5) bond length is 1.77 Å. The Mo(2)-O(6) bond length is 1.78 Å. The Mo(2)-O(7) bond length is 1.79 Å. The Mo(2)-O(8) bond length is 1.86 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Er(2) and one Mo(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Er(1) and one Mo(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Er(1), one Er(2), and one Mo(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Er(1), one Er(2), and one Mo(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Er(2) and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to one Er(1) and one Mo(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Er(2) and one Mo(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Er(1), one Er(2), and one Mo(2) atom. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a water-like geometry to two equivalent Er(1) atoms. In the second Br site, Br(2) is bonded in a distorted bent 120 degrees geometry to one Er(1) and one Er(2) atom.