Crystal structure of an unknown solvate of dodecakis(μ2-alaninato-1:2κ2 O:N,O)cerium(III)hexanickel(II) aquatris(hydroxido-κO)tris(nitrato-κ2 O,O′)cerate(III)

The chiral title compound, [CeNi6(C3H6NO2)12][Ce(NO3)3(OH)3(H2O)], comprises a complex heterometallic Ni/Ce cation and a homonuclear Ce anion. Both the cation and anion exhibit point group symmetry 3. with the CeIII atom situated on the threefold rotation axis. The cation metal core consists of six NiII atoms coordinated in a slightly distorted octahedral N2O4 configuration by N and O atoms of 12 deprotonated l-alaninate ligands exhibiting both bridging and chelating modes. This metal–organic coordination motif encapsulates one CeIII atom that shows an icosahedral coordination by the O-donor atoms of the l-alaninate ligands, with Ce—O distances varying in the range 2.455 (5)–2.675 (3) Å. In the anion, the central CeIII ion is bound to three bidentate nitrate ligands, to three hydroxide ligands and to one water molecule, with Ce—O distances in the range 2.6808 (19)–2.741 (2) Å. The H atoms of the coordinating water molecule are disordered over three positions due to its location on a threefold rotation axis. Disorder is also observed in fragments of two l-alaninate ligands, with occupancy ratios of 0.608 (14):0.392 (14) and 0.669 (8):0.331 (8), respectively, for the two sets of sites. In the crystal, the complex cations and anions assemble through O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional network with large voids of approximately 1020 Å3. The contributions of highly disordered ethanol and water solvent molecules to the diffraction data were removed with the SQUEEZE procedure [Spek (2015 ▸). Acta Cryst. C71, 9–18]. The given chemical formula and other crystal data do not take into account the unknown amount of these solvent molecules.


Related literature
Molecular magnets based on 3d-4f heterometallic constituents can be prepared easily by self-assembling of simple building blocks such as d-metal amino acid salts and lanthanide nitrates (Peristeraki et al., 2011;Yukawa et al., 2005;Igarashi et al., 2000). For an icosahedral coordination environment observed in similar compounds, see: Peristeraki et al. (2011); Zhang et al. (2004). For background to and application of the SQUEEZE procedure, see: Spek (2015

S1. Experimental
Crystals of the title complex were obtained in the course of several days after addition of a Ce(NO 3 ) 3 solution in a waterethanol-methanol mixture to an aquous solution of Ni II L-alaninate.

S2. Refinement
The title complex crystallizes in a chiral space group due to the presence of optically pure L-alanine in the cation.
A region of electron density was treated with the SQUEEZE procedure in PLATON (Spek, 2015). The total potential solvent-accessible void volume is 1020.6 Å 3 , with an estimated electron count of 437. This accounts to approximately 12-15 disordered solvent ethanol and 6-9 water molecules. Their contributions to the total intensity data were removed.
The given chemical formula and other crystal data do not take into account the amount of the unknown solvent molecules.
A part of the L-alaninato ligands were found to be disordered over two sets of sites with refined component ratios of fragment. Disorder was also observed for the coordinating water molecule (O3) situated on a threefold rotation axis.
Owing to symmetry restraints the attached hydrogen atoms are disordered over three sites with an occupancy of onethirds each.
Hydrogen atoms involved in hydrogen bonds (H1, H11B, H12D, and H13B) were located from difference maps and   The coordination polyhedron of Ce2 in the complex cation of the title compound. Displacement ellipsoids are shown at the 50% probability level. A and B indicate symmetry operators -y + 3, x -y + 4, z and -x + y, -x + 3, z, respectively.   Hydrogen-bonding interactions (dotted lines) between the anion and cations.

Dodecakis(µ 2 -alaninato-1:2κ 2 O:N,O)cerium(III)hexanickel(II) aquatris(hydroxido-κO)tris(nitratoκ 2 O,O′)cerate(III)
Crystal data where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.003 Δρ max = 0.57 e Å −3 Δρ min = −0.69 e Å −3 Absolute structure: Flack (1983), 3493 Friedel pairs Absolute structure parameter: −0.012 (11) Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
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