(Butane-1,2,3,4-tetraol-κ(3) O (1),O (2),O (3))(ethanol-κO)tris-(nitrato-κ(2) O,O')erbium(III).

In the title Er(III)-erythritol complex, [Er(NO3)3(C2H5OH)(C4H10O4)], the Er(III) cation is chelated by one erythritol mol-ecule, three nitrate anions and an ethanol mol-ecule, completing an irregular ErO10 coordination geometry. The Er-O bond lengths are in the range 2.348 (3)-2.583 (3) Å. In the crystal, extensive O-H⋯O hydrogen bonding links the mol-ecules into a three-dimensional supra-molecular structure.

[(2R,3S)-Butane-1,2,3,4-tetraol-κ(3) O (1),O (2),O (3)](ethanol-κO)tris-(nitrato-κ(2) O,O')samarium(III).

The title Sm(III)-erythritol complex, [Sm(NO3)3(C2H6O)(C4H10O4)], is isotypic with its Nd, Eu, Y, Gd, Tb and Ho analogues. The Sm(III) cation exhibits a coordination number of ten and is chelated by a tridentate erythritol ligand and three bidentate nitrate anions. It is additionally coordinated by an O atom of an ethanol mol-ecule, completing an irregular coordination sphere. The Sm-O bond lengths range from 2.416 (2) to 2.611 (2) Å. In the crystal, extensive O-H⋯O hydrogen bonding involving all hy-droxy groups and some of the nitrate O atoms links the mol-ecules into a three-dimensional network.

(Butane-1,2,3,4-tetraol-κ(3) O (1),O (2),O (3))(ethanol-κO)tris-(nitrato-κ(2) O,O')holmium(III).

In the title Ho(III)-erythritol complex, [Ho(NO3)3(C4H10O4)(C2H5OH)], the Ho(III) cation is chelated by a tridentate erythritol ligand and three bidentate nitrate anions. An ethanol mol-ecule further coordinates the Ho(III) cation, completing the irregular O10 coordination geometry. In the crystal, an extensive O-H⋯O hydrogen-bond network links the mol-ecules into a three-dimensional supra-molecular structure.

catena-Poly[[[tetra-aqua-neodymium(III)]-di-µ-isonicotinato] chloride].

In the title complex, {[Nd(C(6)H(4)NO(2))(2)(H(2)O)(4)]Cl}(n), the Nd(III) cation is located on a twofold rotation axis and coordinated by four isonicotiniate anions and four water mol-ecules in a distorted square-anti-prismatic geometry. The carboxyl-ate groups of the isonicotinate anions bridge the Nd(III) cations, forming polymeric chains running along the c axis. The Cl(-) anion is located on a twofold rotation axis and is linked to the polymeric chains via O-H⋯Cl hydrogen bonding. Inter-molecular O-H⋯O and O-H⋯N hydrogen bonds are also present in the crystal structure.