research communications
of hydroxy scandium nitrate chloride
aSandia National Laboratories, Advanced Materials Laboratory, 1001 University, Boulevard, SE, Albuquerque, NM 87106, USA, and bUniversity of Hawaii - Manoa, Department of Chemistry, 2545 McCarthy Mall, Honolulu, HI 96822-2275, USA
*Correspondence e-mail: tjboyle@sandia.gov
Each Sc3+ ion in the title salt, di-μ-hydroxido-bis[triaqua(nitrato-κ2O,O′)scandium(III)] dichloride, [Sc2(NO3)2(OH)2(H2O)6]Cl2, is coordinated by a nitrate anion, two hydroxide ions and three water molecules to generate a distorted pentagonal–bipyramidal ScO7 The complete {[(NO3)(μ-OH)Sc(H2O)3]2}2+ ion is generated by crystallographic inversion symmetry. The nitrate anion binds in a bidentate fashion whereas the hydroxide ions are bridged between two Sc centers. Two charge-balancing Cl− ions are located in the outer sphere. In the extended structure, O—H⋯O and O—H⋯Cl hydrogen bonds connect the components into a three-dimensional network.
Keywords: scandium; heptacoordinate; nitrate; crystal structure.
CCDC reference: 1904826
1. Chemical context
Scandium nitrate compounds have found widespread utility in a diverse number of applications, including catalysts for aqueous-based organic reactions (Kobayashi, 1999), heterogeneous catalysts (Cao et al., 2015), cyanosilylation catalysis (Zhang et al., 2015) and films for use in optics and electronic manufacturing (Wang et al., 2013). Previously, the structural properties of scandium salts were reviewed and the wide variety of structure types available for Sc metal were presented (Sears et al., 2017). From this review, the diversity of structurally characterized scandium nitrate salts was illuminated. These were found to possess inner-sphere, outer-sphere and mixed-sphere nitrate ions. Additionally, a number of bridging ligands (OH−, OMe−) were present. As we continue to explore the fundamental coordination behavior of scandium with nitric acid as a means to recycle this multipurpose metal, another unusual scandium nitrate structure [(κ2-NO3)(μ-OH)Sc(H2O)3]22(Cl) (1) was isolated. This report details the structure and its relationship to known scandium nitrate derivatives.
2. Structural commentary
The title compound (Fig. 1) is the third reported hydrated scandium nitrate salt. We previously isolated [(H2O)4Sc(k2-NO3)2](NO3)H2O and [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3) from the reaction of [(H2O)5Sc(μ-OH)]24(Cl)2(H2O) with concentrated nitric acid at elevated and room temperatures, respectively. Similarities between [(k2-NO3)(μ-OH)Sc(H2O)3]22(Cl) and [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3) were expected and observed.
The axial water molecules are distorted from linearity more so for 1 [O1—Sc1—O4 = 166.48 (2)°] than for [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3) [O4—Sc—O6 = 171.52 (7)°]. The Sc—O (H2O) bond distances of 2.124 (1)–2.148 (1) Å for 1 are comparable to the 2.114 (2)–2.183 (1) Å distances reported for the other hydroxide-bridged NO3 salt. Bond angles between the axial water molecules and the remaining nearly coplanar equatorial ligands range from 79.56 (2)–100.60 (2)° for 1 and 82.50 (6)–99.96 (6)° for [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3). The angles between the equatorial oxygen atoms range from 55.61 (2)–81.36 (2)° and 55.76 (5)–83.70 (6)°, respectively. The shortest Sc—O bond distances, 2.0542 (5)–2.0569 (5) Å for 1 and 2.053 (2)–2.076 (1) Å for [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3), occur for the bridging hydroxide ions. In both salts, the bidentate NO3 ions have the weakest interaction with Sc—O bond distances of 2.291 (1)–2.314 (1) Å for 1 and 2.114 (2)–2.183 (1) Å for [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3).
The precursor to 1, [(H2O)5Sc(μ-OH)]24(Cl)2(H2O), is also a seven-coordinate Sc salt. Rotation of the precursor reveals a capped trigonal–prismatic geometry about the Sc centers that is useful for comparison. Equatorial ligand angles for [(H2O)5Sc(μ-OH)]24(Cl)2(H2O) had a much smaller range of 83.32–95.17°. Dihedral angles between axial and equatorial ligands for the precursor also have a significantly reduced range of 77.18–79.09°. These differences further support the distorted pentagonal–bipyramidal geometry assigned to 1.
3. Supramolecular features
A network of scandium hydroxy nitrate dimer chains that interact via separate equatorial coordinated water molecules and nitrate ions with one another is observed for [(k2-NO3)(μ-OH)Sc(H2O)3]22(Cl). These chains are further linked into a three-dimensional network (Fig. 2) by O—H⋯Cl hydrogen bonds between axially as well as equatorially coordinated water molecules and outer sphere Cl− anions indicated by the symmetry operations in Table 1.
4. Database survey
There are two reports of hydrated scandium nitrates, [(H2O)4Sc(k2-NO3)2](NO3)(H2O) (Boyle et al., 2015) and [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3) (Wang et al., 2013; Boyle et al. 2015), and both contain outer-sphere nitrate anions. As expected a similar network is observed for [(H2O)3Sc(k2-NO3)(μ-OH)]22(NO3). Salt 1 is the first reported hydrated scandium nitrate to contain outer-sphere chloride anions.
5. Synthesis and crystallization
Salt 1 was isolated from a cooled (273 K) mixture of [(H2O)5Sc(μ-OH)]24(Cl)2(H2O) dissolved in water and an equal volume of concentrated HNO3(aq). The reaction was slowly warmed to room temperature and set aside for slow evaporation until crystals formed. From this mixture, a single crystal of 1 was selected and used for single crystal X-ray analysis. Note: Both [(H2O)4Sc(κ2-NO3)2]NO3(H2O) and [(H2O)3Sc(κ2-NO3)(μ-OH)]22(NO3) have also been isolated from this preparatory route (Boyle et al., 2015).
6. Refinement
Crystal data, data collection and structure .
details are summarized in Table 2
|
Supporting information
CCDC reference: 1904826
https://doi.org/10.1107/S2056989019003918/hb4231sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989019003918/hb4231Isup2.hkl
Data collection: APEX3 (Bruker, 2016); cell
SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).[Sc2(NO3)2(OH)2(H2O)6]2(Cl) | Z = 1 |
Mr = 426.95 | F(000) = 216 |
Triclinic, P1 | Dx = 1.847 Mg m−3 |
a = 6.7221 (3) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.6279 (4) Å | Cell parameters from 9960 reflections |
c = 8.5181 (4) Å | θ = 2.7–43.4° |
α = 100.904 (2)° | µ = 1.30 mm−1 |
β = 110.125 (2)° | T = 100 K |
γ = 102.329 (2)° | Plate, colourless |
V = 383.87 (3) Å3 | 0.52 × 0.24 × 0.21 mm |
Bruker APEXII CCD diffractometer | 4597 reflections with I > 2σ(I) |
Radiation source: fine–focus tube | Rint = 0.025 |
φ and ω scans | θmax = 42.1°, θmin = 2.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2016) | h = −12→12 |
Tmin = 0.634, Tmax = 0.749 | k = −14→14 |
21806 measured reflections | l = −16→15 |
5393 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.024 | All H-atom parameters refined |
wR(F2) = 0.056 | w = 1/[σ2(Fo2) + (0.026P)2 + 0.0527P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max = 0.001 |
5393 reflections | Δρmax = 0.50 e Å−3 |
119 parameters | Δρmin = −0.35 e Å−3 |
0 restraints |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Sc1 | 0.64421 (2) | 0.20102 (2) | 0.65362 (2) | 0.00619 (2) | |
O1 | 0.77577 (9) | 0.34667 (7) | 0.50248 (7) | 0.01145 (8) | |
H1A | 0.730 (3) | 0.425 (2) | 0.469 (2) | 0.037 (4)* | |
H1B | 0.814 (2) | 0.297 (2) | 0.4330 (19) | 0.031 (4)* | |
O2 | 0.66804 (8) | −0.04815 (7) | 0.53126 (6) | 0.00944 (8) | |
H2 | 0.755 (3) | −0.084 (2) | 0.562 (2) | 0.042 (4)* | |
O3 | 0.97436 (9) | 0.22378 (8) | 0.82658 (7) | 0.01256 (9) | |
H3A | 1.025 (3) | 0.136 (2) | 0.832 (2) | 0.036 (4)* | |
H3B | 1.042 (2) | 0.306 (2) | 0.919 (2) | 0.030 (4)* | |
O4 | 0.54719 (9) | 0.11936 (8) | 0.84788 (7) | 0.01370 (9) | |
H4A | 0.639 (2) | 0.131 (2) | 0.951 (2) | 0.032 (4)* | |
H4B | 0.425 (3) | 0.048 (2) | 0.829 (2) | 0.037 (4)* | |
O5 | 0.77362 (8) | 0.48678 (7) | 0.86375 (7) | 0.01144 (8) | |
O6 | 0.45946 (9) | 0.42130 (7) | 0.64820 (6) | 0.01136 (8) | |
O7 | 0.57811 (11) | 0.68156 (9) | 0.85879 (8) | 0.02282 (13) | |
N1 | 0.60275 (10) | 0.53719 (8) | 0.79388 (8) | 0.01116 (9) | |
Cl1 | 0.09630 (3) | −0.14716 (2) | 0.78189 (2) | 0.01058 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Sc1 | 0.00664 (4) | 0.00485 (4) | 0.00490 (4) | 0.00172 (3) | 0.00048 (3) | 0.00005 (3) |
O1 | 0.0153 (2) | 0.0105 (2) | 0.0118 (2) | 0.00636 (17) | 0.00710 (17) | 0.00454 (16) |
O2 | 0.00739 (17) | 0.00762 (18) | 0.00909 (18) | 0.00341 (14) | −0.00061 (14) | −0.00082 (14) |
O3 | 0.01049 (19) | 0.00957 (19) | 0.0107 (2) | 0.00455 (16) | −0.00204 (16) | −0.00219 (16) |
O4 | 0.0119 (2) | 0.0173 (2) | 0.00861 (19) | 0.00022 (17) | 0.00226 (16) | 0.00464 (17) |
O5 | 0.00943 (18) | 0.00930 (19) | 0.01084 (19) | 0.00451 (15) | −0.00074 (15) | −0.00048 (15) |
O6 | 0.01149 (19) | 0.00946 (19) | 0.00762 (18) | 0.00380 (15) | −0.00085 (15) | −0.00164 (15) |
O7 | 0.0229 (3) | 0.0165 (3) | 0.0196 (3) | 0.0137 (2) | −0.0006 (2) | −0.0075 (2) |
N1 | 0.0113 (2) | 0.0094 (2) | 0.0092 (2) | 0.00476 (17) | 0.00089 (17) | −0.00115 (17) |
Cl1 | 0.01037 (6) | 0.01118 (6) | 0.01048 (6) | 0.00477 (5) | 0.00374 (5) | 0.00283 (5) |
Sc1—O2 | 2.0542 (5) | O2—Sc1i | 2.0569 (5) |
Sc1—O2i | 2.0569 (5) | O2—H2 | 0.692 (16) |
Sc1—O4 | 2.1238 (6) | O3—H3A | 0.815 (16) |
Sc1—O1 | 2.1399 (5) | O3—H3B | 0.811 (15) |
Sc1—O3 | 2.1482 (5) | O4—H4A | 0.859 (15) |
Sc1—O6 | 2.2910 (5) | O4—H4B | 0.824 (16) |
Sc1—O5 | 2.3140 (5) | O5—N1 | 1.2752 (8) |
Sc1—Sc1i | 3.3085 (3) | O6—N1 | 1.2837 (8) |
O1—H1A | 0.782 (16) | O7—N1 | 1.2068 (8) |
O1—H1B | 0.787 (15) | ||
O2—Sc1—O2i | 72.83 (2) | O4—Sc1—Sc1i | 95.494 (17) |
O2—Sc1—O4 | 99.79 (2) | O1—Sc1—Sc1i | 97.895 (16) |
O2i—Sc1—O4 | 89.10 (2) | O3—Sc1—Sc1i | 117.158 (16) |
O2—Sc1—O1 | 92.12 (2) | O6—Sc1—Sc1i | 114.024 (14) |
O2i—Sc1—O1 | 100.60 (2) | O5—Sc1—Sc1i | 168.016 (14) |
O4—Sc1—O1 | 166.48 (2) | Sc1—O1—H1A | 121.1 (11) |
O2—Sc1—O3 | 81.36 (2) | Sc1—O1—H1B | 122.4 (10) |
O2i—Sc1—O3 | 152.16 (2) | H1A—O1—H1B | 107.7 (15) |
O4—Sc1—O3 | 85.12 (2) | Sc1—O2—Sc1i | 107.17 (2) |
O1—Sc1—O3 | 90.41 (2) | Sc1—O2—H2 | 125.6 (14) |
O2—Sc1—O6 | 148.997 (19) | Sc1i—O2—H2 | 125.0 (14) |
O2i—Sc1—O6 | 78.391 (19) | Sc1—O3—H3A | 124.5 (11) |
O4—Sc1—O6 | 90.93 (2) | Sc1—O3—H3B | 122.1 (10) |
O1—Sc1—O6 | 81.93 (2) | H3A—O3—H3B | 108.8 (14) |
O3—Sc1—O6 | 128.81 (2) | Sc1—O4—H4A | 124.1 (10) |
O2—Sc1—O5 | 154.887 (19) | Sc1—O4—H4B | 125.0 (11) |
O2i—Sc1—O5 | 131.997 (19) | H4A—O4—H4B | 108.9 (14) |
O4—Sc1—O5 | 79.56 (2) | N1—O5—Sc1 | 94.62 (4) |
O1—Sc1—O5 | 86.94 (2) | N1—O6—Sc1 | 95.45 (4) |
O3—Sc1—O5 | 73.561 (19) | O7—N1—O5 | 122.93 (6) |
O6—Sc1—O5 | 55.610 (18) | O7—N1—O6 | 122.90 (6) |
O2—Sc1—Sc1i | 36.441 (14) | O5—N1—O6 | 114.17 (5) |
O2i—Sc1—Sc1i | 36.388 (14) | ||
Sc1—O5—N1—O7 | 176.54 (7) | Sc1—O6—N1—O7 | −176.50 (7) |
Sc1—O5—N1—O6 | −3.65 (6) | Sc1—O6—N1—O5 | 3.69 (6) |
Symmetry code: (i) −x+1, −y, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O6ii | 0.782 (16) | 2.051 (16) | 2.8175 (7) | 166.6 (16) |
O1—H1B···Cl1i | 0.787 (15) | 2.300 (15) | 3.0856 (6) | 176.6 (14) |
O2—H2···Cl1iii | 0.692 (16) | 2.617 (16) | 3.2749 (5) | 159.7 (17) |
O3—H3A···Cl1iii | 0.815 (16) | 2.305 (16) | 3.1017 (6) | 165.9 (15) |
O3—H3B···O5iv | 0.811 (15) | 1.989 (15) | 2.7977 (7) | 175.0 (14) |
O4—H4A···Cl1v | 0.859 (15) | 2.316 (15) | 3.1722 (6) | 174.5 (13) |
O4—H4B···Cl1 | 0.824 (16) | 2.242 (16) | 3.0658 (6) | 179.0 (15) |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x+1, y, z; (iv) −x+2, −y+1, −z+2; (v) −x+1, −y, −z+2. |
Funding information
This work was supported by the Laboratory Directed Research and Development program at Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the US Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.
References
Boyle, T. J., Sears, J. M., Neville, M. L., Alam, T. M. & Young, V. G. Jr (2015). Inorg. Chem. 54, 11831–11841. Web of Science CrossRef ICSD CAS PubMed Google Scholar
Bruker (2016). APEX2, SAINT andSADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cao, Y., Zhu, Z., Xu, J., Wang, L., Sun, J., Chen, X. & Fan, Y. (2015). Dalton Trans. 44, 1942–1947. Web of Science CSD CrossRef CAS PubMed Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Kobayashi, S. (1999). Eur. J. Org. Chem. pp. 15–27. CrossRef Google Scholar
Sears, J. M. & Boyle, T. J. (2017). Coord. Chem. Rev. 340, 154–171. Web of Science CrossRef CAS Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Wang, W., Chang, I.-Y., Zakharov, L., Cheong, P. H.-Y. & Keszler, D. A. (2013). Inorg. Chem. 52, 1807–1811. Web of Science CrossRef ICSD CAS PubMed Google Scholar
Zhang, L., Wang, L., Wang, P., Song, T., Li, D., Chen, X., Fan, Y. & Xu, J. (2015). Eur. J. Inorg. Chem. pp. 931–938. Web of Science CSD CrossRef Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.