research communications
Synthesis,
and Hirshfeld surface analysis of sodium bis(malonato)borate monohydrateaDepartment of Physics, Government College for Women (Autonomous), (affiliated to Bharathidasan University), Kumbakonam 612 001, Tamilnadu, India, bPrincipal (Retired), Kunthavai Naacchiyaar Government Arts College for Women (Autonomous), Thanjavur 613 007, Tamilnadu, India, and cDepartment of Physics, Government Arts College (Autonomous), (affiliated to Bharathidasan University), Kumbakonam 612 002, Tamilnadu, India
*Correspondence e-mail: gokilaphy1981@gmail.com, thiruvalluvar.a@gmail.com
In the title salt, poly[aqua[μ4-bis(malonato)borato]sodium], {[Na(C6H4BO8)]·H2O}n or Na+·[B(C3H2O4)2]−·H2O, the sodium cation exhibits fivefold coordination by four carbonyl O atoms of the bis(malonato)borate anions and a water O atom. The tetrahedral B atom at the centre of the anion leads to the formation of a polymeric three-dimensional framework, which is consolidated by C—H⋯O and O—H⋯O hydrogen bonds. A Hirshfeld surface analysis indicates that the most significant contacts in the crystal packing are H⋯O/O⋯H (49.7%), Na⋯O/O⋯Na (16.1%), O⋯O (12.6%), H⋯H (10.7%) and C⋯O/O⋯C (7.3%).
Keywords: synthesis; crystal structure; bis(malonato)borate anion; sodium; Hirshfeld surface analysis..
CCDC reference: 2325391
1. Chemical context
The review by Vaalma et al. (2018) provides a comprehensive overview of the cost and resource implications of sodium-ion batteries, which are a promising alternative to lithium-ion batteries for energy storage applications. The authors conclude that sodium-ion batteries have the potential to be significantly less expensive than lithium-ion batteries, due to the abundance of sodium and the lower cost of sodium-based materials. Allen et al. (2012) described the structure of lithium bis(2-methyllactato)borate monohydrate and there is a growing interest, as highlighted in various recent studies (Vaalma et al., 2018; Abraham, 2020; Li et al., 2019; Wang et al., 2018), in lithium bis(malonato)borate polymers as robust electrolytes.
The present study explores the substitution of 2-methyllactic acid and lithium carbonate with malonic acid and sodium carbonate, respectively, and presents the synthesis, +·[B(C3H2O4)2]−·H2O, (I).
and Hirshfeld surface analysis of the title compound, Na2. Structural commentary
The ). The tetrahedral B atom is bonded to two malonate (C3H2O4) ligands coordinated in an O,O′-bidentate mode.
of (I) comprises a sodium cation, a bis(malonato)borate anion and a coordinated water molecule (Fig. 1In the boron–oxygen tetrahedron, the mean B—O bond length of 1.4641 Å is in good agreement with the expected B(sp3)—O bond length of 1.468 Å (Allen et al., 1987). The largest O—B—O bond angles are the intracyclic angles: O1—B1—O3 = 112.92 (9)° and O5—B1—O7 = 112.21 (9)°. The six-membered boro–malonate rings O1/C1/C2/C3/O3/B1 and O5/C4/C5/C6/O7/B1 both adopt boat conformations [puckering parameters Q = 0.4082 (13) Å, θ = 87.85 (18)° and φ = 309.10 (18)° for the first ring, and Q = 0.4267 (13) Å, θ = 84.32 (16)° and φ = 317.00 (17)° for the second ring]. The `prow and stern' atoms in the first ring, B1 and C2, are displaced by 0.3680 (18) and 0.330 (2) Å, respectively, from C1/C3/O1/O3 (r.m.s. deviation = 0.0323 Å). In the second ring, the equivalent data are a B1 displacement of 0.4048 (17), a C5 displacement of 0.298 (2) Å and an r.m.s. deviation of 0.0621 Å. The dihedral angle between the O1/C1/C3/O3 and O5/C4/C6/O7 least-squares planes is 73.34 (4)°.
Na1 is surrounded by five O atoms [carbonyl O2 and O6 at (x − 1, y, z), water O9, carbonyl O8 at (x − , −y + , z + ) and O6 at (−x + , y − , −z + )], forming a square-based pyramidal (Table 1). A possible sixth bond [Na1—O5 at (x − 1, y, z)], which would generate a distorted octahedron, is much longer at 3.0195 (10) Å and presumably only represents a marginal interaction in the structure.
3. Supramolecular features and Hirshfeld surface analysis
The ). The packing of the structure is shown in Fig. 2.
of (I) is consolidated by two C—H⋯O links with the acceptors being one water O9 atom and one carbonyl O4 atom, and three O—H⋯O links, one of which is bifurcated, with the acceptors being one borate O1 atom and carbonyl atoms O4 and O2 (Table 2
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The Hirshfeld surface analysis of (I) was performed with CrystalExplorer (Version 21.5; Spackman et al., 2021). Fig. 3 shows the dnorm surface for the bis(malonato)borate anion plotted over the limits from −0.66 to +0.93 a.u. The intense red spots represent the shortest intermolecular contacts (attractive interactions like hydrogen bonds) and the blue regions denotes the longest (indicating possible repulsive interactions or regions with weak van der Waals interactions). Fig. 4 presents the two-dimensional fingerprint plots involving all the intermolecular interactions [Fig. 4(a)] and delineated into Na⋯O/O⋯Na = 16.1% [Fig. 4(b)], C⋯O/O⋯C = 7.3% [Fig. 4(c)], H⋯H = 10.7% [Fig. 4(d)], H⋯O/O⋯H = 49.7% [Fig. 4(e)] and O⋯O = 12.6% [Fig. 4(f)] interactions. The remaining interactions contribute less than 2.0%. The hydrogen bonds are indicated by pairs of characteristic wings in the fingerprint plot [Fig. 4(e)] representing H⋯O/O⋯H contacts. Pairs of scattered points of spikes are seen in the fingerprint plot delineated into H⋯O/O⋯H contacts (49.7% the maximum contribution to the Hirshfeld surface) [Fig. 4(e)].
4. Database survey
A search using CCDC ConQuest of the Cambridge Structural Database (CSD, Version 5.44, updated to June 2023; Groom et al., 2016) for the bis(malonato)borate anion gave one hit (CSD refcode PITQUF; Zviedre & Belyakov, 2007), in which the bis(malonato)borate unit is similar to that in (I) and is charge balanced by potassium cations. The K+ coordination geometry in PITQUF is an irregular nine-vertex polyhedron formed by the O atoms of seven complex anions.
5. Synthesis and crystallization
The title compound was synthesized by mixing malonic acid (C3H4O4), boric acid (H3BO3) and sodium carbonate (Na2CO3) in a 4:2:1 molar ratio, using deionized water as the solvent. Initially, malonic acid (4.1264 g) was dissolved in deionized water. This was followed by the addition of a boric acid solution (1.236 g) and then a sodium carbonate solution (1.382 g) was added. The mixture was stirred thoroughly to ensure a uniform solution. The beaker containing the solution was then covered with a perforated sheet and left undisturbed. Over three months, due to slow evaporation of the solvent, small clear crystals of (I) formed at the bottom of the container [yield: 2.744 g, 40.6%; m.p. 527–529 K (decomposition)]. FT–IR (cm−1): 3928, 3856, 3419, 3014, 2908, 2542, 2016, 1711, 1635, 1400, 1334, 1271, 1069, 1019, 958, 914, 859, 833, 657, 634, 561, 478, 457, 423.
6. Refinement
Crystal data and structure . The H atoms attached to C atoms were placed in calculated positions (C—H = 0.97 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C). The water H atoms were located in difference maps and refined with restraints (O—H = 0.84 ± 0.02 Å and H⋯H = 1.36 ± 0.02 Å) to ensure a realistic geometry.
details are summarized in Table 3
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Supporting information
CCDC reference: 2325391
[Na(C6H4BO8)(H2O)] | F(000) = 520 |
Mr = 255.91 | Dx = 1.806 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 7.9058 (4) Å | Cell parameters from 9951 reflections |
b = 8.2979 (5) Å | θ = 2.8–30.5° |
c = 14.6473 (9) Å | µ = 0.21 mm−1 |
β = 101.565 (2)° | T = 298 K |
V = 941.38 (9) Å3 | Block, colourless |
Z = 4 | 0.35 × 0.27 × 0.27 mm |
Bruker D8 VENTURE diffractometer with a PHOTON II detector | 2494 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.030 |
ω and φ scan | θmax = 30.5°, θmin = 3.6° |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | h = −10→11 |
Tmin = 0.917, Tmax = 0.958 | k = −11→11 |
32209 measured reflections | l = −20→20 |
2864 independent reflections |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | Hydrogen site location: mixed |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0503P)2 + 0.3262P] where P = (Fo2 + 2Fc2)/3 |
2864 reflections | (Δ/σ)max < 0.001 |
162 parameters | Δρmax = 0.53 e Å−3 |
4 restraints | Δρmin = −0.60 e Å−3 |
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 | ||
Na1 | 0.24488 (7) | 0.47538 (7) | 0.76584 (4) | 0.03728 (15) | |
B1 | 0.76757 (17) | 0.52073 (15) | 0.55156 (9) | 0.0271 (2) | |
C1 | 0.59169 (15) | 0.47853 (15) | 0.66789 (9) | 0.0294 (2) | |
C2 | 0.64385 (17) | 0.30481 (15) | 0.66658 (9) | 0.0331 (3) | |
H2A | 0.551966 | 0.239128 | 0.681940 | 0.040* | |
H2B | 0.745590 | 0.288268 | 0.715054 | 0.040* | |
C3 | 0.68228 (16) | 0.24605 (14) | 0.57587 (9) | 0.0309 (2) | |
C4 | 1.01449 (13) | 0.68524 (13) | 0.61701 (7) | 0.0235 (2) | |
C5 | 0.93606 (17) | 0.81205 (14) | 0.54883 (9) | 0.0340 (3) | |
H5A | 1.028548 | 0.875823 | 0.532601 | 0.041* | |
H5B | 0.867448 | 0.883229 | 0.579401 | 0.041* | |
C6 | 0.82428 (16) | 0.75128 (16) | 0.46059 (9) | 0.0331 (3) | |
O1 | 0.64336 (12) | 0.57513 (11) | 0.60743 (7) | 0.0337 (2) | |
O2 | 0.50736 (14) | 0.53111 (13) | 0.72169 (8) | 0.0451 (3) | |
O3 | 0.74511 (13) | 0.35276 (11) | 0.52435 (7) | 0.0358 (2) | |
O4 | 0.66050 (17) | 0.10738 (13) | 0.55087 (9) | 0.0518 (3) | |
O5 | 0.94362 (11) | 0.54098 (10) | 0.60778 (6) | 0.02768 (18) | |
O6 | 1.13921 (12) | 0.71217 (11) | 0.67822 (6) | 0.0329 (2) | |
O7 | 0.74022 (12) | 0.61563 (12) | 0.46608 (6) | 0.0366 (2) | |
O8 | 0.80823 (17) | 0.82359 (17) | 0.38773 (8) | 0.0577 (3) | |
O9 | 0.00848 (15) | 0.39690 (13) | 0.82757 (8) | 0.0448 (3) | |
H9A | −0.008 (4) | 0.443 (3) | 0.8765 (14) | 0.088 (9)* | |
H9B | 0.019 (4) | 0.2983 (16) | 0.8397 (19) | 0.100 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Na1 | 0.0334 (3) | 0.0373 (3) | 0.0430 (3) | 0.0070 (2) | 0.0124 (2) | 0.0112 (2) |
B1 | 0.0289 (6) | 0.0257 (6) | 0.0283 (6) | −0.0034 (4) | 0.0090 (5) | −0.0002 (4) |
C1 | 0.0242 (5) | 0.0316 (6) | 0.0337 (6) | −0.0052 (4) | 0.0089 (4) | −0.0065 (4) |
C2 | 0.0401 (6) | 0.0291 (6) | 0.0316 (6) | −0.0021 (5) | 0.0107 (5) | 0.0008 (4) |
C3 | 0.0322 (5) | 0.0252 (5) | 0.0360 (6) | −0.0037 (4) | 0.0086 (4) | −0.0039 (4) |
C4 | 0.0255 (4) | 0.0238 (5) | 0.0219 (4) | 0.0022 (4) | 0.0062 (4) | 0.0025 (4) |
C5 | 0.0391 (6) | 0.0234 (5) | 0.0355 (6) | −0.0004 (4) | −0.0022 (5) | 0.0087 (5) |
C6 | 0.0310 (5) | 0.0382 (6) | 0.0286 (6) | 0.0004 (5) | 0.0025 (4) | 0.0120 (5) |
O1 | 0.0349 (4) | 0.0249 (4) | 0.0456 (5) | 0.0004 (3) | 0.0180 (4) | −0.0013 (4) |
O2 | 0.0423 (5) | 0.0478 (6) | 0.0527 (6) | −0.0066 (4) | 0.0272 (5) | −0.0150 (5) |
O3 | 0.0458 (5) | 0.0288 (4) | 0.0375 (5) | −0.0077 (4) | 0.0198 (4) | −0.0079 (4) |
O4 | 0.0722 (8) | 0.0270 (5) | 0.0611 (7) | −0.0110 (5) | 0.0249 (6) | −0.0122 (5) |
O5 | 0.0295 (4) | 0.0236 (4) | 0.0292 (4) | −0.0007 (3) | 0.0042 (3) | 0.0075 (3) |
O6 | 0.0332 (4) | 0.0349 (4) | 0.0274 (4) | −0.0009 (3) | −0.0016 (3) | 0.0013 (3) |
O7 | 0.0369 (4) | 0.0411 (5) | 0.0282 (4) | −0.0087 (4) | −0.0017 (3) | 0.0066 (4) |
O8 | 0.0601 (7) | 0.0713 (8) | 0.0370 (6) | −0.0081 (6) | −0.0020 (5) | 0.0315 (6) |
O9 | 0.0525 (6) | 0.0366 (5) | 0.0487 (6) | −0.0035 (4) | 0.0181 (5) | 0.0039 (5) |
Na1—O9 | 2.3264 (12) | C2—H2A | 0.9700 |
Na1—O2 | 2.3402 (11) | C2—H2B | 0.9700 |
Na1—O6i | 2.4032 (10) | C3—O4 | 1.2094 (16) |
Na1—O8ii | 2.4213 (12) | C3—O3 | 1.3231 (15) |
Na1—O6iii | 2.4455 (11) | C4—O6 | 1.2130 (14) |
Na1—O5i | 3.0195 (10) | C4—O5 | 1.3171 (13) |
B1—O3 | 1.4508 (15) | C4—C5 | 1.4969 (15) |
B1—O7 | 1.4581 (16) | C5—C6 | 1.4993 (18) |
B1—O1 | 1.4697 (15) | C5—H5A | 0.9700 |
B1—O5 | 1.4779 (15) | C5—H5B | 0.9700 |
C1—O2 | 1.2109 (15) | C6—O8 | 1.2086 (15) |
C1—O1 | 1.3186 (15) | C6—O7 | 1.3177 (16) |
C1—C2 | 1.5005 (17) | O9—H9A | 0.846 (13) |
C2—C3 | 1.5024 (17) | O9—H9B | 0.838 (13) |
O9—Na1—O2 | 171.38 (5) | O4—C3—C2 | 122.33 (12) |
O9—Na1—O6i | 102.48 (4) | O3—C3—C2 | 116.93 (10) |
O2—Na1—O6i | 85.61 (4) | O6—C4—O5 | 120.62 (10) |
O9—Na1—O8ii | 88.27 (5) | O6—C4—C5 | 122.02 (10) |
O2—Na1—O8ii | 90.22 (5) | O5—C4—C5 | 117.36 (10) |
O6i—Na1—O8ii | 80.15 (4) | O6—C4—Na1iv | 45.91 (6) |
O9—Na1—O6iii | 84.03 (4) | O5—C4—Na1iv | 74.82 (6) |
O2—Na1—O6iii | 88.60 (4) | C5—C4—Na1iv | 167.29 (8) |
O6i—Na1—O6iii | 167.40 (3) | C4—C5—C6 | 115.62 (10) |
O8ii—Na1—O6iii | 111.10 (5) | C4—C5—H5A | 108.4 |
O9—Na1—O5i | 77.10 (4) | C6—C5—H5A | 108.4 |
O2—Na1—O5i | 111.06 (4) | C4—C5—H5B | 108.4 |
O6i—Na1—O5i | 46.12 (3) | C6—C5—H5B | 108.4 |
O8ii—Na1—O5i | 117.12 (4) | H5A—C5—H5B | 107.4 |
O6iii—Na1—O5i | 127.08 (4) | O8—C6—O7 | 120.86 (13) |
O3—B1—O7 | 107.10 (10) | O8—C6—C5 | 122.25 (13) |
O3—B1—O1 | 112.92 (9) | O7—C6—C5 | 116.88 (10) |
O7—B1—O1 | 108.16 (10) | C1—O1—B1 | 121.25 (10) |
O3—B1—O5 | 108.18 (10) | C1—O2—Na1 | 137.99 (9) |
O7—B1—O5 | 112.21 (9) | C3—O3—B1 | 121.70 (10) |
O1—B1—O5 | 108.33 (10) | C4—O5—B1 | 119.62 (9) |
O2—C1—O1 | 120.21 (12) | C4—O5—Na1iv | 80.28 (6) |
O2—C1—C2 | 122.89 (12) | B1—O5—Na1iv | 156.45 (7) |
O1—C1—C2 | 116.90 (10) | C4—O6—Na1iv | 112.84 (8) |
C1—C2—C3 | 115.33 (11) | C4—O6—Na1v | 127.34 (8) |
C1—C2—H2A | 108.4 | Na1iv—O6—Na1v | 118.98 (3) |
C3—C2—H2A | 108.4 | C6—O7—B1 | 121.60 (10) |
C1—C2—H2B | 108.4 | C6—O8—Na1vi | 164.30 (13) |
C3—C2—H2B | 108.4 | Na1—O9—H9A | 118 (2) |
H2A—C2—H2B | 107.5 | Na1—O9—H9B | 108 (2) |
O4—C3—O3 | 120.73 (12) | H9A—O9—H9B | 107 (2) |
O2—C1—C2—C3 | 156.38 (13) | C5—C4—O5—B1 | −17.36 (15) |
O1—C1—C2—C3 | −24.22 (16) | Na1iv—C4—O5—B1 | 166.54 (9) |
C1—C2—C3—O4 | −150.74 (13) | O6—C4—O5—Na1iv | −3.33 (10) |
C1—C2—C3—O3 | 30.58 (17) | C5—C4—O5—Na1iv | 176.10 (10) |
O6—C4—C5—C6 | 160.61 (11) | O3—B1—O5—C4 | 159.43 (9) |
O5—C4—C5—C6 | −18.81 (16) | O7—B1—O5—C4 | 41.49 (14) |
Na1iv—C4—C5—C6 | 143.8 (3) | O1—B1—O5—C4 | −77.85 (12) |
C4—C5—C6—O8 | −150.46 (14) | O3—B1—O5—Na1iv | −55.6 (2) |
C4—C5—C6—O7 | 30.90 (17) | O7—B1—O5—Na1iv | −173.55 (12) |
O2—C1—O1—B1 | 170.39 (12) | O1—B1—O5—Na1iv | 67.1 (2) |
C2—C1—O1—B1 | −9.02 (16) | O5—C4—O6—Na1iv | 4.47 (13) |
O3—B1—O1—C1 | 35.76 (16) | C5—C4—O6—Na1iv | −174.93 (9) |
O7—B1—O1—C1 | 154.11 (10) | O5—C4—O6—Na1v | −164.81 (7) |
O5—B1—O1—C1 | −84.03 (13) | C5—C4—O6—Na1v | 15.79 (16) |
O1—C1—O2—Na1 | 126.39 (13) | Na1iv—C4—O6—Na1v | −169.29 (12) |
C2—C1—O2—Na1 | −54.2 (2) | O8—C6—O7—B1 | 175.44 (14) |
O4—C3—O3—B1 | 178.15 (13) | C5—C6—O7—B1 | −5.90 (18) |
C2—C3—O3—B1 | −3.14 (18) | O3—B1—O7—C6 | −147.33 (11) |
O7—B1—O3—C3 | −147.88 (11) | O1—B1—O7—C6 | 90.69 (14) |
O1—B1—O3—C3 | −28.92 (17) | O5—B1—O7—C6 | −28.75 (16) |
O5—B1—O3—C3 | 90.96 (13) | O7—C6—O8—Na1vi | 117.5 (4) |
O6—C4—O5—B1 | 163.22 (10) | C5—C6—O8—Na1vi | −61.0 (5) |
Symmetry codes: (i) x−1, y, z; (ii) x−1/2, −y+3/2, z+1/2; (iii) −x+3/2, y−1/2, −z+3/2; (iv) x+1, y, z; (v) −x+3/2, y+1/2, −z+3/2; (vi) x+1/2, −y+3/2, z−1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2B···O9iv | 0.97 | 2.54 | 3.4247 (18) | 151 |
C5—H5B···O4vii | 0.97 | 2.46 | 3.2830 (18) | 143 |
O9—H9A···O4viii | 0.85 (1) | 2.23 (2) | 2.9932 (17) | 151 (3) |
O9—H9B···O1ix | 0.84 (1) | 2.46 (2) | 3.1520 (14) | 140 (3) |
O9—H9B···O2ix | 0.84 (1) | 2.39 (2) | 3.1166 (17) | 146 (3) |
Symmetry codes: (iv) x+1, y, z; (vii) x, y+1, z; (viii) −x+1/2, y+1/2, −z+3/2; (ix) −x+1/2, y−1/2, −z+3/2. |
Acknowledgements
The authors thank the Sophisticated Analytical Instrument Facility (SAIF), Indian Institute of Technology Madras (IITM), Chennai, Tamilnadu, India, for the single-crystal X-ray diffraction data.
References
Abraham, K. M. (2020). ACS Energy Lett. 5, 3544–3547. CrossRef CAS Google Scholar
Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
Allen, J. L., Paillard, E., Boyle, P. D. & Henderson, W. A. (2012). Acta Cryst. E68, m749. CSD CrossRef IUCr Journals Google Scholar
Bruker (2021). APEX3, SAINT/XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3–10. Web of Science CSD CrossRef ICSD CAS IUCr Journals Google Scholar
Li, K., Zhang, J., Lin, D., Wang, D.-W., Li, B., Lv, W., Sun, S., He, Y.-B., Kang, F., Yang, Q.-H., Zhou, L. & Zhang, T.-Y. (2019). Nat. Commun. 10, 725. CrossRef PubMed 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
Spackman, P. R., Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Jayatilaka, D. & Spackman, M. A. (2021). J. Appl. Cryst. 54, 1006–1011. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2020). Acta Cryst. E76, 1–11. Web of Science CrossRef IUCr Journals Google Scholar
Vaalma, C., Buchholz, D., Weil, M. & Passerini, S. (2018). Nat. Rev. Mater. 3, 18013. CrossRef Google Scholar
Wang, T., Su, D., Shanmukaraj, D., Rojo, T., Armand, M. & Wang, G. (2018). Electrochem. Energy Rev. 1, 200–237. CrossRef CAS Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zviedre, I. I. & Belyakov, S. V. (2007). Russ. J. Inorg. Chem. 52, 686–690. CrossRef Google Scholar
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