research communications
of bis(dimethylammonium) hexaaquanickel(II) bis(sulfate) dihydrate
aInstitut für Kristallographie, Universität zu Köln, Greinstrasse 6, D-50939 Köln, Germany
*Correspondence e-mail: peter.held@uni-koeln.de
In the title salt, (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O, the NiII cation is located on a centre of inversion and exhibits a slightly distorted octahedral arrangement of water molecules. The Ni—O bond lengths in the complex [Ni(H2O)6]2+ cation show a distribution as in the related Tutton salt (NH4)2[Ni(H2O)6](SO4)2, but are longer in average [2.056 (13) versus 2.037 (12) Å]. The noncoordinating water molecules and dimethylammonium cations connect the sulfate and [Ni(H2O)6]2+ octahedra via O—H⋯O and N—H⋯O hydrogen bonds from weak up to medium strength into a three-dimensional framework whereby the complex metal cations and sulfate anions are arranged in sheets parallel (001).
Keywords: crystal structure; dimethylammonium salt; hexaaquanickel(II) salt; sulfate; hydrogen bonding.
CCDC reference: 1028557
1. Chemical context
In the course of a systematic search for new `double salts' of simple secondary 3)2NH2][Cu(HSO4)(SO4)(H2O)4] has been described previously (Held, 2014). In continuation of these studies, copper(II) was replaced by nickel(II), yielding crystals of the title compound with composition (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O.
and divalent cations of various inorganic acids, the structure of [(CH2. Structural commentary
The 2(CH3)]+ cation, one Ni2+ cation situated on an inversion centre (Wyckoff position 4a), one SO42− anion and four water molecules, one of which is not coordinating to the metal cation (Fig. 1). The NiII cation exhibits a slightly distorted octahedral arrangement of the water molecules. The Ni—O distances show the same bond lengths distribution [mean 2.055 (12) Å], as in the related Tutton salt (NH4)2[Ni(H2O)6](SO4)2 (Grimes et al., 1963), but are slightly longer (Δd = 0.02 Å). The NiII cation reaches an overall bond valence sum (Brown & Altermatt, 1985) of 2.03 valence units. The S—O distances are nearly equal [mean 1.463 (8) Å], however, the O—S—O angles vary clearly [average bond angle 109.5 (8)°].
of the title compound consists of one [NH3. Supramolecular features
Hydrogen bonds of weak up to medium strength involving coordinating and noncoordinating water molecules as donor groups and O atoms of the sulfate anions as acceptor groups interconnect neighbouring [Ni(H2O)6]2+ octahedra. Together with relatively weaker N—H⋯O hydrogen bonds of the ammonium H atoms to sulfate anions, a three-dimensional framework is formed with pronounced formation of sheets of complex metal cations and sulfate anions parallel (001) (Table 1 and Fig. 2).
4. Synthesis and crystallization
The title compound was obtained by reaction of an aqueous solution of nickel(II) sulfate with dimethylamine and sulfuric acid (18 mol l−1) in a stoichiometric ratio of 1:2:1. The resulting solution was kept at room temperature by cooling. The title compound crystallized by slow evaporation of the solvent at room temperature in form of light-green crystals with dimensions up to 4 mm within 12 weeks.
5. Refinement
Details of structure . All H atoms were clearly discernible from difference Fourier maps. However, riding-model contraints were applied to all H atoms in the least-squares with C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C) for methyl H atoms, and N—H = 0.90 Å and Uiso(H) = 1.2Ueq(N) for ammonium H atoms. The H atoms of water molecules were refined with a distance restraint of O—H = 0.98 Å and individual Uiso values for each H atom.
are given in Table 2
|
Supporting information
CCDC reference: 1028557
10.1107/S160053681402234X/wm5074sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681402234X/wm5074Isup2.hkl
In the course of a systematic search for new `double salts' of simple secondary
and divalent cations of various inorganic acids, the structure of [(CH3)2NH2][Cu(HSO4)(SO4)(H2O)4] has been described previously (Held, 2014). In continuation of these studies, copper(II) was replaced by nickel(II), yielding crystals of the title compound with composition (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O.The
of the title compound consists of one [NH2(CH3)]+ cation, one Ni2+ cation situated on an inversion centre (Wyckoff position 4a), one SO42- anion and four water molecules, one of which is not coordinating to the metal cation (Fig. 1). The NiII cation exhibits a slightly distorted octahedral arrangement of the water molecules. The Ni—O distances show the same bond lengths distribution [mean 2.055 (12) Å], as in the related Tutton salt (NH4)2[Ni(H2O)6)](SO4)2 (Grimes et al., 1963), but are slightly longer (Δd = 0.02 Å). The NiII cation reaches an overall bond valence sum (Brown & Altermatt, 1985) of 2.03 valence units. The S—O distances are nearly equal [mean 1.463 (8) Å], however, the O—S—O angles vary clearly [average bond angle 109.5 (8)°].Hydrogen bonds of weak up to medium strength involving coordinating and noncoordinating water molecules as donor groups and O atoms of the sulfate anions as acceptor groups interconnect neighbouring [Ni(H2O)6]2+ octahedra. Together with relatively weaker N—H···O hydrogen bonds of the ammonium H atoms to sulfate anions, a three-dimensional framework is formed with pronounced formation of sheets of complex metal cations and sulfate anions parallel (001) (Table 1 and Fig. 2).
The title compound was obtained by reaction of an aqueous solution of nickel(II) sulfate with dimethylamine and sulfuric acid (18 mol l-1) in a stoichiometric ratio of 1:2:1. The resulting solution was kept at room temperature by cooling. The title compound crystallized by slow evaporation of the solvent at room temperature in form of light-green crystals with dimensions up to 4 mm within 12 weeks.
Details of structure
are given in Table 1. All H atoms were clearly discernible from difference Fourier maps. However, riding-model contraints were applied to all H atoms in the least-squares with C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C) for methyl H atoms, and N—H = 0.90 Å and Uiso(H) = 1.2Ueq(N) for ammonium H atoms. The H atoms of water molecules were refined with a distance restraint of O—H = 0.98 Å and individual Uiso values for each H atom.Data collection: CAD-4 Software (Enraf–Nonius, 1998); cell
CAD-4 Software (Enraf–Nonius, 1998); data reduction: MolEN (Fair, 1990); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ATOMS (Dowty, 2011); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and puplCIF (Westrip, 2010).The molecular entities in the structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (i) -x, -y+1, -z-1.] (100)-projection of the of the title compound. Colour scheme: (SO4) tetrahedra yellow, [Ni(OH2)6] octahedra red, O blue, N green, C grey and H colourless. H···O bonds up to 1.8 Å are given as orange dashed lines and from 1.85 to 2.7 Å as light-blue dashed lines. |
(C2H8N)2[Ni(H2O)6](SO4)2·2H2O | F(000) = 1032 |
Mr = 487.13 | Dx = 1.660 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 25 reflections |
a = 8.9363 (6) Å | θ = 5.5–10.1° |
b = 13.2370 (8) Å | µ = 1.28 mm−1 |
c = 16.4810 (14) Å | T = 295 K |
V = 1949.5 (2) Å3 | Prism, light green |
Z = 4 | 0.29 × 0.27 × 0.26 mm |
Enraf–Nonius MACH3 diffractometer | 962 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.107 |
Graphite monochromator | θmax = 25.0°, θmin = 2.5° |
/w2/q scans | h = −10→10 |
Absorption correction: ψ scan (North et al., 1968) | k = −15→15 |
Tmin = 0.935, Tmax = 0.999 | l = −19→19 |
4902 measured reflections | 3 standard reflections every 100 reflections |
1719 independent reflections | intensity decay: 0.3% |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.123 | w = 1/[σ2(Fo2) + (0.0578P)2 + 0.0324P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
1719 reflections | Δρmax = 0.44 e Å−3 |
148 parameters | Δρmin = −0.41 e Å−3 |
8 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0267 (19) |
(C2H8N)2[Ni(H2O)6](SO4)2·2H2O | V = 1949.5 (2) Å3 |
Mr = 487.13 | Z = 4 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 8.9363 (6) Å | µ = 1.28 mm−1 |
b = 13.2370 (8) Å | T = 295 K |
c = 16.4810 (14) Å | 0.29 × 0.27 × 0.26 mm |
Enraf–Nonius MACH3 diffractometer | 962 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.107 |
Tmin = 0.935, Tmax = 0.999 | 3 standard reflections every 100 reflections |
4902 measured reflections | intensity decay: 0.3% |
1719 independent reflections |
R[F2 > 2σ(F2)] = 0.040 | 8 restraints |
wR(F2) = 0.123 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.44 e Å−3 |
1719 reflections | Δρmin = −0.41 e Å−3 |
148 parameters |
Experimental. A suitable single-crystal was carefully selected under a polarizing microscope and mounted in a glass capillary. |
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 F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Ni | 0.0000 | 0.5000 | −0.5000 | 0.0269 (3) | |
S1 | 0.44455 (15) | 0.65768 (10) | −0.40485 (8) | 0.0314 (4) | |
O1 | 0.3690 (4) | 0.7003 (3) | −0.4766 (2) | 0.0446 (11) | |
O2 | 0.3354 (4) | 0.6104 (3) | −0.3508 (2) | 0.0424 (11) | |
O3 | 0.5247 (5) | 0.7376 (3) | −0.3626 (3) | 0.0617 (13) | |
O4 | 0.5509 (6) | 0.5805 (3) | −0.4313 (3) | 0.0764 (16) | |
O5 | −0.0494 (5) | 0.4469 (3) | −0.6145 (2) | 0.0382 (10) | |
H51 | −0.150 (3) | 0.420 (4) | −0.619 (3) | 0.06 (2)* | |
H52 | 0.023 (7) | 0.401 (5) | −0.639 (5) | 0.12 (3)* | |
O6 | 0.1383 (4) | 0.6054 (3) | −0.5541 (2) | 0.0339 (9) | |
H61 | 0.090 (6) | 0.656 (3) | −0.588 (3) | 0.07 (2)* | |
H62 | 0.209 (5) | 0.639 (4) | −0.518 (3) | 0.07 (2)* | |
O7 | 0.1783 (4) | 0.4042 (3) | −0.4930 (2) | 0.0379 (9) | |
H71 | 0.264 (4) | 0.415 (5) | −0.528 (3) | 0.07 (2)* | |
H72 | 0.169 (9) | 0.3310 (10) | −0.490 (4) | 0.11 (3)* | |
O8 | 0.1689 (5) | 0.3224 (4) | −0.6862 (2) | 0.0535 (12) | |
H81 | 0.275 (2) | 0.311 (5) | −0.676 (4) | 0.10 (3)* | |
H82 | 0.177 (10) | 0.361 (5) | −0.736 (3) | 0.12 (3)* | |
N3 | 0.0336 (6) | 0.1126 (4) | −0.6424 (3) | 0.0537 (15) | |
H3A | 0.1022 | 0.1550 | −0.6213 | 0.064* | |
H3B | 0.0189 | 0.0628 | −0.6061 | 0.064* | |
C1 | 0.0946 (11) | 0.0689 (5) | −0.7152 (5) | 0.097 (3) | |
H1A | 0.1864 | 0.0346 | −0.7027 | 0.145* | |
H1B | 0.1138 | 0.1214 | −0.7541 | 0.145* | |
H1C | 0.0243 | 0.0216 | −0.7375 | 0.145* | |
C2 | −0.1071 (8) | 0.1681 (6) | −0.6520 (5) | 0.071 (2) | |
H2A | −0.1374 | 0.1951 | −0.6005 | 0.106* | |
H2B | −0.1830 | 0.1231 | −0.6720 | 0.106* | |
H2C | −0.0930 | 0.2223 | −0.6899 | 0.106* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni | 0.0289 (5) | 0.0233 (5) | 0.0284 (5) | 0.0004 (5) | −0.0020 (4) | 0.0003 (5) |
S1 | 0.0293 (7) | 0.0309 (7) | 0.0340 (8) | −0.0008 (6) | −0.0010 (6) | 0.0055 (6) |
O1 | 0.055 (3) | 0.040 (2) | 0.038 (2) | −0.009 (2) | −0.0177 (19) | 0.0099 (18) |
O2 | 0.031 (2) | 0.053 (3) | 0.043 (2) | −0.0083 (19) | 0.0059 (19) | 0.007 (2) |
O3 | 0.083 (3) | 0.054 (3) | 0.047 (3) | −0.033 (3) | −0.027 (2) | 0.015 (2) |
O4 | 0.066 (3) | 0.059 (3) | 0.104 (4) | 0.026 (3) | 0.040 (3) | 0.029 (3) |
O5 | 0.032 (2) | 0.045 (2) | 0.038 (2) | −0.005 (2) | −0.0017 (19) | −0.0058 (19) |
O6 | 0.036 (2) | 0.029 (2) | 0.037 (2) | −0.0031 (18) | −0.0059 (18) | 0.0067 (18) |
O7 | 0.032 (2) | 0.032 (2) | 0.050 (3) | 0.0070 (18) | 0.008 (2) | 0.007 (2) |
O8 | 0.041 (3) | 0.080 (3) | 0.040 (3) | −0.003 (3) | 0.000 (2) | −0.008 (3) |
N3 | 0.069 (4) | 0.041 (3) | 0.051 (3) | 0.004 (3) | −0.016 (3) | −0.005 (3) |
C1 | 0.147 (9) | 0.049 (5) | 0.094 (7) | 0.008 (5) | 0.065 (6) | 0.013 (4) |
C2 | 0.051 (4) | 0.078 (6) | 0.082 (5) | −0.001 (4) | 0.011 (4) | 0.021 (5) |
Ni—O7i | 2.040 (3) | O7—H71 | 0.974 (10) |
Ni—O7 | 2.040 (3) | O7—H72 | 0.975 (10) |
Ni—O5 | 2.061 (4) | O8—H81 | 0.975 (10) |
Ni—O5i | 2.061 (4) | O8—H82 | 0.976 (10) |
Ni—O6 | 2.066 (4) | N3—C1 | 1.440 (8) |
Ni—O6i | 2.066 (4) | N3—C2 | 1.464 (8) |
S1—O3 | 1.455 (4) | N3—H3A | 0.9000 |
S1—O4 | 1.461 (4) | N3—H3B | 0.9000 |
S1—O2 | 1.461 (4) | C1—H1A | 0.9600 |
S1—O1 | 1.474 (4) | C1—H1B | 0.9600 |
O5—H51 | 0.974 (10) | C1—H1C | 0.9600 |
O5—H52 | 0.976 (10) | C2—H2A | 0.9600 |
O6—H61 | 0.973 (10) | C2—H2B | 0.9600 |
O6—H62 | 0.976 (10) | C2—H2C | 0.9600 |
O7i—Ni—O7 | 180.0 (2) | Ni—O6—H62 | 116 (4) |
O7i—Ni—O5 | 89.60 (16) | H61—O6—H62 | 109 (5) |
O7—Ni—O5 | 90.40 (16) | Ni—O7—H71 | 119 (4) |
O7i—Ni—O5i | 90.40 (16) | Ni—O7—H72 | 123 (5) |
O7—Ni—O5i | 89.60 (16) | H71—O7—H72 | 104 (6) |
O5—Ni—O5i | 180.0 | H81—O8—H82 | 99 (6) |
O7i—Ni—O6 | 91.33 (15) | C1—N3—C2 | 115.8 (6) |
O7—Ni—O6 | 88.67 (15) | C1—N3—H3A | 108.3 |
O5—Ni—O6 | 87.90 (15) | C2—N3—H3A | 108.3 |
O5i—Ni—O6 | 92.10 (15) | C1—N3—H3B | 108.3 |
O7i—Ni—O6i | 88.67 (15) | C2—N3—H3B | 108.3 |
O7—Ni—O6i | 91.33 (15) | H3A—N3—H3B | 107.4 |
O5—Ni—O6i | 92.10 (15) | N3—C1—H1A | 109.5 |
O5i—Ni—O6i | 87.90 (15) | N3—C1—H1B | 109.5 |
O6—Ni—O6i | 180.00 (19) | H1A—C1—H1B | 109.5 |
O3—S1—O4 | 109.3 (3) | N3—C1—H1C | 109.5 |
O3—S1—O2 | 110.4 (3) | H1A—C1—H1C | 109.5 |
O4—S1—O2 | 108.4 (3) | H1B—C1—H1C | 109.5 |
O3—S1—O1 | 109.3 (2) | N3—C2—H2A | 109.5 |
O4—S1—O1 | 109.0 (3) | N3—C2—H2B | 109.5 |
O2—S1—O1 | 110.3 (2) | H2A—C2—H2B | 109.5 |
Ni—O5—H51 | 113 (3) | N3—C2—H2C | 109.5 |
Ni—O5—H52 | 117 (5) | H2A—C2—H2C | 109.5 |
H51—O5—H52 | 110 (6) | H2B—C2—H2C | 109.5 |
Ni—O6—H61 | 117 (4) |
Symmetry code: (i) −x, −y+1, −z−1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H51···O2i | 0.97 (1) | 1.77 (2) | 2.727 (5) | 166 (5) |
O5—H52···O8 | 0.98 (1) | 1.84 (1) | 2.814 (6) | 176 (7) |
O6—H61···O3ii | 0.97 (1) | 1.73 (2) | 2.689 (5) | 169 (6) |
O6—H62···O1 | 0.98 (1) | 1.78 (2) | 2.731 (5) | 164 (5) |
O7—H71···O4iii | 0.97 (1) | 1.78 (2) | 2.730 (6) | 164 (5) |
O7—H72···O1iv | 0.98 (1) | 1.78 (2) | 2.745 (5) | 173 (7) |
O8—H81···O3iii | 0.98 (1) | 2.01 (2) | 2.962 (6) | 166 (6) |
O8—H82···O2v | 0.98 (1) | 1.93 (3) | 2.856 (6) | 158 (7) |
N3—H3B···O4vi | 0.90 | 2.02 | 2.835 (7) | 151 |
N3—H3A···O6iv | 0.90 | 2.65 | 3.274 (6) | 127 |
Symmetry codes: (i) −x, −y+1, −z−1; (ii) x−1/2, −y+3/2, −z−1; (iii) −x+1, −y+1, −z−1; (iv) −x+1/2, y−1/2, z; (v) −x+1/2, −y+1, z−1/2; (vi) x−1/2, −y+1/2, −z−1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H51···O2i | 0.974 (10) | 1.772 (19) | 2.727 (5) | 166 (5) |
O5—H52···O8 | 0.976 (10) | 1.840 (13) | 2.814 (6) | 176 (7) |
O6—H61···O3ii | 0.973 (10) | 1.728 (16) | 2.689 (5) | 169 (6) |
O6—H62···O1 | 0.976 (10) | 1.78 (2) | 2.731 (5) | 164 (5) |
O7—H71···O4iii | 0.974 (10) | 1.78 (2) | 2.730 (6) | 164 (5) |
O7—H72···O1iv | 0.975 (10) | 1.776 (15) | 2.745 (5) | 173 (7) |
O8—H81···O3iii | 0.975 (10) | 2.01 (2) | 2.962 (6) | 166 (6) |
O8—H82···O2v | 0.976 (10) | 1.93 (3) | 2.856 (6) | 158 (7) |
N3—H3B···O4vi | 0.90 | 2.02 | 2.835 (7) | 150.8 |
N3—H3A···O6iv | 0.90 | 2.65 | 3.274 (6) | 127.0 |
Symmetry codes: (i) −x, −y+1, −z−1; (ii) x−1/2, −y+3/2, −z−1; (iii) −x+1, −y+1, −z−1; (iv) −x+1/2, y−1/2, z; (v) −x+1/2, −y+1, z−1/2; (vi) x−1/2, −y+1/2, −z−1. |
Experimental details
Crystal data | |
Chemical formula | (C2H8N)2[Ni(H2O)6](SO4)2·2H2O |
Mr | 487.13 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 295 |
a, b, c (Å) | 8.9363 (6), 13.2370 (8), 16.4810 (14) |
V (Å3) | 1949.5 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.28 |
Crystal size (mm) | 0.29 × 0.27 × 0.26 |
Data collection | |
Diffractometer | Enraf–Nonius MACH3 diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.935, 0.999 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4902, 1719, 962 |
Rint | 0.107 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.123, 1.07 |
No. of reflections | 1719 |
No. of parameters | 148 |
No. of restraints | 8 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.44, −0.41 |
Computer programs: CAD-4 Software (Enraf–Nonius, 1998), MolEN (Fair, 1990), SIR97 (Altomare et al., 1999), ATOMS (Dowty, 2011), SHELXL97 (Sheldrick, 2008) and puplCIF (Westrip, 2010).
References
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