metal-organic compounds
Bis(diisopropylammonium) hexachloridostannate(IV)
aInstitut für Anorganische Chemie und Strukturchemie, Lehrstuhl II: Material- und Strukturforschung, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
*Correspondence e-mail: reissg@hhu.de
The title compound, (C6H16N)2[SnCl6], crystallizes with one diisopropylammonium cation lying on a general position and the hexachloridostannate(IV) anion about a centre of inversion. The [SnCl6]2− anion undergoes a slight distortion from octahedral symmetry as the result of the formation of four unforked charge-supported N—H⋯Cl hydrogen bonds. The hydrogen bonds between the cations and anions form layers perpendicular to [101]. These layers are built by 24-membered rings which can be classified with an R88(24) graph-set descriptor. According to this hydrogen-bonding motif, the title compound is isostructural with (C6H16N)2[IrCl6].
Related literature
For related diisopropylammonium salts, see: Fu et al. (2011); Reiss (1998, 2002, 2012); Reiss & Helmbrecht (2012); Reiss & Meyer (2011). For layered structures, see: Cameron et al. (1983); Holl & Thewalt (1986); Rademeyer et al. (2007). For potassium hexahalogenidometalates, see: Abrahams et al. (1989); Amilius et al. (1969); Boysen & Hewat (1978); Coll et al. (1987); Hinz et al. (2000). For spectroscopy of hexachloridostannate(IV) salts, see: Brown et al. (1970); Ouasri et al. (2001). For graph-set theory and its applications, see: Etter et al. (1990); Grell et al. (2002).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2012); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536812043371/mw2089sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812043371/mw2089Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812043371/mw2089Isup3.mol
(dipH)2[SnCl6] was prepared by dissolving 208 mg (2.05 mmol) diisopropylamine and 360 mg (1.02 mmol) tin(IV) chloride in 5 mL of concentrated hydrochloric acid (37 percent). In one to two days under ambient conditions colourless rhombic crystals were obtained by slow evaporation of the solvent. The Raman spectrum was measured using a Bruker MULTIRAM spectrometer (Nd:YAG-Laser at 1064 nm; RT-InGaAs-detector; resolution: 2 cm-1); 4000–70 cm-1: 3140(w), 3087(w), 2994(s), 2982(m, sh), 2970(m), 2948(m), 2908(m), 2700(w), 1574(w), 1479(w), 1458(m), 1411(w), 1342(w), 1296(w), 1196 (w, sh), 1184(w), 1168(w), 1142(w), 1084(w), 968(w), 957(w), 912(w), 880(vw), 824(w), 799(m), 468(w), 439(w), 309(vs; ν1, Sn–Cl), 235 (m, br; ν2, Sn–Cl), 170 (s; ν4, Sn–Cl), 159 (s; ν5, Sn–Cl), 77 (m; lattice mode). – IR spectroscopic data were recorded on a Digilab FT3400 spectrometer using a MIRacle ATR unit (Pike Technologies); 4000–560 cm-1: 3134(vs), 3082(s), 2991(m), 2981(m), 2969(m), 2945(w), 2835(w, br), 2712(w), 2442(w), 2391(w), 1620(w, br), 1573(s), 1472(w), 1466(w), 1458(w), 1425(m), 1395(s), 1384(m), 1358(w), 1342(vw), 1316(w), 1196(w), 1183(m), 1166(w), 1141(m), 1097(m), 969(w), 943(w), 877(w), 824(w), 798(vw).
All hydrogen atoms were identified in difference syntheses. The hydrogen atoms of the methyl groups were idealized and refined using rigid groups allowed to rotate about the C—C bond (AFIX 137 option of the SHELXL97 programme). For each methyl group one common Uiso value was refined. The coordinates of hydrogen atoms belonging to the CH and NH2 groups were refined freely. The Uiso(H) values of the two hydrogen atoms of the NH2 group were refined unrestricted.
Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell
CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2012); software used to prepare material for publication: publCIF (Westrip, 2010).(C6H16N)2[SnCl6] | F(000) = 540 |
Mr = 535.81 | Dx = 1.573 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 8237 reflections |
a = 9.54362 (13) Å | θ = 2.9–36.3° |
b = 11.98179 (19) Å | µ = 1.83 mm−1 |
c = 9.90669 (14) Å | T = 100 K |
β = 92.9406 (14)° | Plate, colourless |
V = 1131.33 (3) Å3 | 0.33 × 0.27 × 0.08 mm |
Z = 2 |
Oxford Diffraction Xcalibur Eos diffractometer | 4972 independent reflections |
Radiation source: fine-focus sealed tube | 4468 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
Detector resolution: 16.2711 pixels mm-1 | θmax = 35.0°, θmin = 2.9° |
ω scans | h = −15→15 |
Absorption correction: numerical (CrysAlis PRO; Oxford Diffraction, 2009) | k = −19→19 |
Tmin = 0.634, Tmax = 0.922 | l = −12→15 |
11414 measured reflections |
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)] = 0.021 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.048 | w = 1/[σ2(Fo2) + (0.0186P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.001 |
4972 reflections | Δρmax = 0.53 e Å−3 |
120 parameters | Δρmin = −0.57 e Å−3 |
0 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: 0.0041 (4) |
(C6H16N)2[SnCl6] | V = 1131.33 (3) Å3 |
Mr = 535.81 | Z = 2 |
Monoclinic, P21/n | Mo Kα radiation |
a = 9.54362 (13) Å | µ = 1.83 mm−1 |
b = 11.98179 (19) Å | T = 100 K |
c = 9.90669 (14) Å | 0.33 × 0.27 × 0.08 mm |
β = 92.9406 (14)° |
Oxford Diffraction Xcalibur Eos diffractometer | 4972 independent reflections |
Absorption correction: numerical (CrysAlis PRO; Oxford Diffraction, 2009) | 4468 reflections with I > 2σ(I) |
Tmin = 0.634, Tmax = 0.922 | Rint = 0.024 |
11414 measured reflections |
R[F2 > 2σ(F2)] = 0.021 | 0 restraints |
wR(F2) = 0.048 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.53 e Å−3 |
4972 reflections | Δρmin = −0.57 e Å−3 |
120 parameters |
Experimental. Absorption correction: CrysAlisPro (Oxford Diffraction, 2009). Numerical absorption correction based on gaussian integration over a multifaceted crystal model. |
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. |
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 | ||
Sn1 | 1.0000 | 0.0000 | 0.0000 | 0.01123 (3) | |
Cl1 | 0.92766 (3) | 0.08742 (2) | 0.20722 (2) | 0.01631 (6) | |
Cl2 | 1.11712 (3) | 0.17373 (2) | −0.06094 (3) | 0.01646 (6) | |
Cl3 | 0.78698 (3) | 0.06606 (2) | −0.11335 (3) | 0.01563 (5) | |
N1 | 0.68736 (10) | 0.27997 (8) | 0.11589 (10) | 0.01418 (17) | |
H11 | 0.7445 (17) | 0.2227 (14) | 0.1090 (15) | 0.025 (4)* | |
H12 | 0.6727 (16) | 0.2895 (13) | 0.2005 (15) | 0.025 (4)* | |
C1 | 0.54865 (11) | 0.24787 (9) | 0.04603 (11) | 0.01420 (19) | |
H1 | 0.5701 (16) | 0.2361 (12) | −0.0494 (14) | 0.017* | |
C2 | 0.44162 (12) | 0.33988 (10) | 0.06181 (12) | 0.0186 (2) | |
H2A | 0.4352 | 0.3571 | 0.1559 | 0.025 (2)* | |
H2B | 0.3517 | 0.3155 | 0.0251 | 0.025 (2)* | |
H2C | 0.4702 | 0.4053 | 0.0144 | 0.025 (2)* | |
C3 | 0.50358 (13) | 0.13875 (10) | 0.10779 (13) | 0.0213 (2) | |
H3A | 0.5742 | 0.0831 | 0.0957 | 0.025 (2)* | |
H3B | 0.4166 | 0.1148 | 0.0642 | 0.025 (2)* | |
H3C | 0.4914 | 0.1492 | 0.2025 | 0.025 (2)* | |
C4 | 0.75609 (12) | 0.38701 (10) | 0.07441 (12) | 0.0171 (2) | |
H4 | 0.6925 (16) | 0.4433 (13) | 0.0962 (14) | 0.020* | |
C5 | 0.89127 (14) | 0.40009 (12) | 0.16051 (14) | 0.0272 (3) | |
H5A | 0.8715 | 0.3948 | 0.2543 | 0.036 (3)* | |
H5B | 0.9321 | 0.4716 | 0.1432 | 0.036 (3)* | |
H5C | 0.9557 | 0.3422 | 0.1384 | 0.036 (3)* | |
C6 | 0.78081 (14) | 0.38572 (12) | −0.07562 (12) | 0.0238 (2) | |
H6A | 0.8376 | 0.3224 | −0.0961 | 0.035 (3)* | |
H6B | 0.8281 | 0.4530 | −0.0997 | 0.035 (3)* | |
H6C | 0.6924 | 0.3809 | −0.1260 | 0.035 (3)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Sn1 | 0.01016 (5) | 0.01241 (5) | 0.01133 (5) | 0.00038 (3) | 0.00261 (3) | 0.00032 (3) |
Cl1 | 0.01780 (12) | 0.01875 (12) | 0.01260 (10) | 0.00316 (9) | 0.00306 (9) | −0.00157 (9) |
Cl2 | 0.01694 (12) | 0.01595 (12) | 0.01663 (11) | −0.00356 (9) | 0.00218 (9) | 0.00126 (9) |
Cl3 | 0.01222 (10) | 0.01879 (12) | 0.01588 (11) | 0.00180 (9) | 0.00070 (9) | 0.00081 (10) |
N1 | 0.0125 (4) | 0.0154 (4) | 0.0148 (4) | 0.0002 (3) | 0.0028 (3) | 0.0007 (4) |
C1 | 0.0133 (4) | 0.0151 (5) | 0.0143 (4) | −0.0012 (4) | 0.0026 (4) | −0.0016 (4) |
C2 | 0.0156 (5) | 0.0187 (5) | 0.0215 (5) | 0.0019 (4) | 0.0005 (4) | −0.0009 (4) |
C3 | 0.0207 (5) | 0.0159 (5) | 0.0280 (6) | −0.0038 (4) | 0.0079 (5) | 0.0012 (5) |
C4 | 0.0151 (5) | 0.0135 (5) | 0.0231 (5) | −0.0024 (4) | 0.0048 (4) | −0.0016 (4) |
C5 | 0.0198 (6) | 0.0310 (7) | 0.0307 (6) | −0.0091 (5) | 0.0012 (5) | −0.0068 (6) |
C6 | 0.0235 (6) | 0.0242 (6) | 0.0243 (6) | −0.0051 (5) | 0.0073 (5) | 0.0059 (5) |
Sn1—Cl3i | 2.4055 (3) | C2—H2B | 0.9600 |
Sn1—Cl3 | 2.4055 (3) | C2—H2C | 0.9600 |
Sn1—Cl1 | 2.4359 (3) | C3—H3A | 0.9600 |
Sn1—Cl1i | 2.4359 (3) | C3—H3B | 0.9600 |
Sn1—Cl2 | 2.4527 (3) | C3—H3C | 0.9600 |
Sn1—Cl2i | 2.4527 (3) | C4—C6 | 1.5168 (16) |
N1—C4 | 1.5073 (15) | C4—C5 | 1.5178 (17) |
N1—C1 | 1.5117 (14) | C4—H4 | 0.940 (16) |
N1—H11 | 0.881 (16) | C5—H5A | 0.9600 |
N1—H12 | 0.864 (15) | C5—H5B | 0.9600 |
C1—C3 | 1.5153 (16) | C5—H5C | 0.9600 |
C1—C2 | 1.5164 (16) | C6—H6A | 0.9600 |
C1—H1 | 0.988 (14) | C6—H6B | 0.9600 |
C2—H2A | 0.9600 | C6—H6C | 0.9600 |
Cl3i—Sn1—Cl3 | 180.000 (18) | H2A—C2—H2B | 109.5 |
Cl3i—Sn1—Cl1 | 90.994 (9) | C1—C2—H2C | 109.5 |
Cl3—Sn1—Cl1 | 89.006 (9) | H2A—C2—H2C | 109.5 |
Cl3i—Sn1—Cl1i | 89.006 (9) | H2B—C2—H2C | 109.5 |
Cl3—Sn1—Cl1i | 90.994 (9) | C1—C3—H3A | 109.5 |
Cl1—Sn1—Cl1i | 180.000 (13) | C1—C3—H3B | 109.5 |
Cl3i—Sn1—Cl2 | 90.528 (9) | H3A—C3—H3B | 109.5 |
Cl3—Sn1—Cl2 | 89.472 (9) | C1—C3—H3C | 109.5 |
Cl1—Sn1—Cl2 | 89.711 (9) | H3A—C3—H3C | 109.5 |
Cl1i—Sn1—Cl2 | 90.289 (9) | H3B—C3—H3C | 109.5 |
Cl3i—Sn1—Cl2i | 89.472 (9) | N1—C4—C6 | 110.50 (9) |
Cl3—Sn1—Cl2i | 90.528 (9) | N1—C4—C5 | 107.69 (10) |
Cl1—Sn1—Cl2i | 90.289 (9) | C6—C4—C5 | 112.41 (10) |
Cl1i—Sn1—Cl2i | 89.711 (9) | N1—C4—H4 | 104.7 (9) |
Cl2—Sn1—Cl2i | 180.000 (13) | C6—C4—H4 | 111.5 (9) |
C4—N1—C1 | 118.34 (9) | C5—C4—H4 | 109.7 (9) |
C4—N1—H11 | 111.2 (10) | C4—C5—H5A | 109.5 |
C1—N1—H11 | 107.3 (10) | C4—C5—H5B | 109.5 |
C4—N1—H12 | 104.2 (11) | H5A—C5—H5B | 109.5 |
C1—N1—H12 | 107.3 (10) | C4—C5—H5C | 109.5 |
H11—N1—H12 | 108.0 (14) | H5A—C5—H5C | 109.5 |
N1—C1—C3 | 107.14 (9) | H5B—C5—H5C | 109.5 |
N1—C1—C2 | 110.28 (9) | C4—C6—H6A | 109.5 |
C3—C1—C2 | 112.27 (10) | C4—C6—H6B | 109.5 |
N1—C1—H1 | 104.8 (9) | H6A—C6—H6B | 109.5 |
C3—C1—H1 | 109.9 (9) | C4—C6—H6C | 109.5 |
C2—C1—H1 | 112.1 (9) | H6A—C6—H6C | 109.5 |
C1—C2—H2A | 109.5 | H6B—C6—H6C | 109.5 |
C1—C2—H2B | 109.5 | ||
C4—N1—C1—C3 | −179.42 (9) | C1—N1—C4—C6 | −57.67 (13) |
C4—N1—C1—C2 | −56.96 (12) | C1—N1—C4—C5 | 179.20 (10) |
Symmetry code: (i) −x+2, −y, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11···Cl1 | 0.881 (16) | 2.541 (16) | 3.3449 (10) | 152.1 (13) |
N1—H12···Cl2ii | 0.864 (15) | 2.488 (15) | 3.3507 (10) | 176.0 (14) |
Symmetry code: (ii) x−1/2, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | (C6H16N)2[SnCl6] |
Mr | 535.81 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 100 |
a, b, c (Å) | 9.54362 (13), 11.98179 (19), 9.90669 (14) |
β (°) | 92.9406 (14) |
V (Å3) | 1131.33 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.83 |
Crystal size (mm) | 0.33 × 0.27 × 0.08 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur Eos diffractometer |
Absorption correction | Numerical (CrysAlis PRO; Oxford Diffraction, 2009) |
Tmin, Tmax | 0.634, 0.922 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11414, 4972, 4468 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.807 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.021, 0.048, 1.02 |
No. of reflections | 4972 |
No. of parameters | 120 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.53, −0.57 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2012), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11···Cl1 | 0.881 (16) | 2.541 (16) | 3.3449 (10) | 152.1 (13) |
N1—H12···Cl2i | 0.864 (15) | 2.488 (15) | 3.3507 (10) | 176.0 (14) |
Symmetry code: (i) x−1/2, −y+1/2, z+1/2. |
Acknowledgements
We thank E. Hammes for technical support. We acknowledge the support for the publication fee by the Deutsche Forschungsgemeinschaft (DFG) and the open-access publication fund of the Heinrich-Heine-Universität Düsseldorf.
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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.
Even though there are more than one hundred diisopropylammonium (dipH) salt structures listed in the Cambridge Crystallographic Data Base only a limited number of halogenidometalate-containing salts are reported: [SiF6]2- (Reiss, 1998); [IrCl6]2- (Reiss, 2002); [FeCl4]- (Reiss, 2012), [CuCl4]2- (Reiss & Helmbrecht, 2012). Recently the simple dipH chloride has attracted much attention as it is a ferroelectric solid with a high phase transition temperature (Fu et al., 2011). This study on (dipH)2[SnCl6] is part of our long standing interest on the principles of arrangement of simple dipH salts (Reiss & Meyer, 2011).
The title compound (dipH)2[SnCl6] crystallizes with one dipH cation in a general position and one [SnCl6]2- anion located on a center of inversion. The C–N and C–C bond lengths and the bond angles of the cation are in the expected range. The [SnCl6]2- anion adopts a distorted octahedral geometry (angles between 89.00 (1) and 91.00 (1)°). The cations and anions are connected by medium-strong, charge-supported hydrogen bonds (Table 1) between the NH2+ groups and their neighbouring chlorine atoms (Fig. 1). Only four out of six chlorido ligands of each [SnCl6]2- anion are involved with the Sn–Cl bonds participating in hydrogen bonding significantly longer (2.4359 (3) and 2.4527 (3) Å) than the two others (2.4055 (3) Å). This bonding situation results in the formation of two-dimensional layers in the [101] plane, whose characteristic motif is an annealed, 24-membered, wavy, hydrogen bonded ring (Fig. 1) with the graph-set descriptor R88(24) (Etter et al., 1990). This second level graph-set is shown in Fig. 2 as part of the constructor graph (Grell et al. 2002). The two other representative second level graph-sets are C44(12) which run along [11–1] and C22(6) which represents the bent connection of one [SnCl6]2- anion with two dipH cations. The shortest H···Cl distance of the Cl3 is with 2.938 (16) Å roughly 0.5 Å longer than the two other H···Cl bonds. The acute N-H···Cl3 angle of 131.7 (12) ° supports our interpretation that the Cl3 atom is not involved in any significant hydrogen bond.
Analogous layered structures are also known for other (RnNH4-n)2[SnCl6] salts and have been discussed in detail (Holl & Thewalt, 1986; Cameron et al. 1983, Rademeyer et al. 2007).With the title compound featuring 24-membered hydrogen bonded rings, composed of four [SnCl6]2- anions and four dipH ions, it is isostructural but not isotypical to (dipH)2[IrCl6] (Reiss, 2002). Whilst in (dipH)2[IrCl6] two crystallographically independent layers are present, in the title structure identical crystallographically dependent layers are stacked. The difference between the two structures is in the ring size of 11.9818 (2) / 14.1040 (2) Å (Fig. 1) for the latter and only 10.396 (1) / 13.638 (1) Å for the former and seems to be due to a more simple packing of the bulky isopropyl groups in the title structure. A structural relationship between the (dipH)2[IrCl6] and the K3[MoCl6] types of structures (Amilius et al., 1969; Coll et al., 1987; Hinz et al., 2000) has been discussed (Reiss, 2002). In this structural family, the directly related higher symmetry K2[TeBr6] type (Abrahams et al., 1989; Boysen & Hewat, 1978) exists which could be similarly compared to the title structure.
The Raman spectrum of (dipH)2[SnCl6] shows the Raman-active bands (ν1, ν2 and ν5) of the [SnCl6]2- anions. Additionally a medium-strong band at 170 cm-1 is assigned to the ν4 mode which becomes Raman-active due to the distortion of the [SnCl6]2- anion (Ouasri et al. 2001). Furthermore the band at 77 cm-1 represents a characteristic lattice mode for related compounds (Brown et al., 1970).