research communications
3)3]2[Ag(NH3)2]2[SnF6]F2, a compound showing argentophilic interactions
of [Ag(NHaAnorganische Chemie, Fluorchemie, Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35032 Marburg, Germany
*Correspondence e-mail: florian.kraus@chemie.uni-marburg.de
Bis[triamminesilver(I)] bis[diamminesilver(I)] hexafluoridostannate(IV) difluoride, [Ag(NH3)3]2[Ag(NH3)2]2[SnF6]F2, was obtained in the form of colourless crystals from the reaction of CsAgSnF7 in anhydrous ammonia. Two different ammine complexes of silver(I) are present in the structure, i.e. a linear diammine and a T-shaped triammine complex. The ammine silver(I) complexes show Ag⋯Ag distances in the range of argentophilic interactions. In the crystal, several N—H⋯F hydrogen bonds are present between the complex cations and the SbF6− and F− anions, leading to the formation of a three-dimensional network.
Keywords: crystal structure; silver; argentophilic interactions; fluorides; ammine ligand.
CCDC reference: 1519625
1. Chemical context
Metallophilicity, especially argento- and aurophilicity, is a theoretically and experimentally well-established concept, see, for example, the seminal works of Jansen (Jansen, 1987), Schmidbaur and co-workers (Scherbaum et al., 1988; Schmidbaur, 1995; Schmidbaur & Schier, 2012, 2015) or Pyykkö and co-workers (Pyykkö & Zhao, 1991; Pyykkö, 1997,2004; Pyykkö et al., 1997; Pyykkö & Mendizabal, 1997). We reacted a silver(II) compound, CsAgSnF7, with anhydrous liquid ammonia and observed the reduction of AgII. The preparation conditions and of the thus obtained AgI title compound, [Ag(NH3)3]2[Ag(NH3)2]2[SnF6]F2, is reported here. The short Ag⋯Ag distances between the complex cations are in the range of argentophilic interactions.
2. Structural commentary
[Ag(NH3)3]2[Ag(NH3)2]2[SnF6]F2 crystallizes in type P21/c. The Sn atom occupies 2d (site symmetry ), all other atoms reside on general positions 4e. The structure comprises of [Ag(NH3)3]+ and [Ag(NH3)2]+ complex cations as well as F− and [SnF6]2− anions (Fig. 1). The diamminesilver(I) cation (Ag2) is almost linear with an N—Ag—N angle of 170.93 (7)° and Ag—N distances of 2.1160 (16) and 2.1183 (16) Å. The deviation from linearity is likely to arise from the surrounding, i.e. N—H⋯F hydrogen bonding to adjacent [SnF6]2− and F− anions. This [Ag(NH3)2]+ cation shows a short Ag⋯Ag distance of 3.0611 (2) Å to a neighboring [Ag(NH3)3]+ cation and another slightly longer Ag⋯Ag distance of 3.3282 (2) Å to a second [Ag(NH3)3]+ cation (symmetry code x, −y + , z + ). The triammine silver(I) cation (Ag1) is T-shaped and can be viewed as a linear diammine silver(I) cation to which another ammine ligands is bound at a longer distance. The short Ag—N distances are 2.1434 (16) and 2.1662 (16) Å, and the remote ammine ligand is bound at a distance of 2.5870 (19) Å. The N—Ag—N angle between the shortly bonded ligands is 173.74 (7)°. The deviation of N—Ag—N angles including the remote ammine ligand from 90° [85.44 (6) and 110.82 (6)°] are probably due to hydrogen bonding of the ammine ligands to F atoms of the anions.
3. Supramolecular features
As a result of the short Ag1⋯Ag2 contacts, corrugated strands of alternating [Ag(NH3)3]+ and [Ag(NH3)2]+ cations occur where the [Ag(NH3)3]+ cations form the kinks which are connected by the [Ag(NH3)2]+ cations. The strands run parallel to the c axis (Fig. 2). Similar metallophilic interactions have been observed in the ammine copper(I) fluoride {[Cu(NH3)3]2[Cu2(NH3)4]}F4·4NH3 (Woidy et al., 2015). However, the cuprophilic interactions are only observed between the diammine copper(I) cations forming linear strands whereas the triammine copper(I) cations do not show such interactions.
In the title structure, the fluoride anions reside above and below the cation strands and connect neighbouring strands via N—H⋯F hydrogen bonds, whereas the [SnF6]2− anions lie on the sides of the strands, also connecting neighbouring ones. The free fluoride ion (F4) is an acceptor of six hydrogen bonds (Fig. 3). Its coordination environment resembles an octahedron with one longer edge. It interconnects the Ag⋯Ag strands along the a-axis. The [SnF6]2− anion interconnects four of the Ag⋯Ag strands (Fig. 4). Four of the six F atoms bonded to the Sn atom are acceptors of four hydrogen bonds (two regular, two bifurcated), the other two F atoms are acceptors of three hydrogen bonds. The diammine silver(I) cations only form regular hydrogen bonds, whereas the triammine silver(I) cations form regular as well as bifurcated hydrogen bonds. The bifurcated hydrogen bonds bridge four edges of each [SnF6]2− octahedron. Overall, a rather complex three-dimensional hydrogen-bonded network results (Fig. 5). Numerical details of the hydrogen-bonding interactions are summarized in Table 1.
4. Synthesis and crystallization
870 mg of CsAgSnF7 were reacted with approximately 10 ml of anhydrous liquid ammonia at 195 K. Upon contact, the greenish colour of the educt vanished and a white powder was observed. This indicates that AgII was reduced to AgI and ammonia was oxidized to N2. From this white powder, colorless crystals grew within three months of storage at 233 K of which a suitable one was selected for the diffraction experiment. The role of the Cs atoms remains unclear.
5. Refinement
Crystal data, data collection and structure . Hydrogen atoms were localized from difference Fourier syntheses and were refined freely.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1519625
https://doi.org/10.1107/S2056989016019010/wm5342sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989016019010/wm5342Isup2.hkl
Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell
CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015) and SHELXLE (Hübschle et al., 2011); molecular graphics: DIAMOND (Brandenburg, 2012); software used to prepare material for publication: publCIF (Westrip, 2010).[Ag(NH3)3]2[Ag(NH3)2]2[SnF6]F2 | F(000) = 820 |
Mr = 872.51 | Dx = 2.815 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 7.3274 (2) Å | Cell parameters from 16653 reflections |
b = 19.4495 (4) Å | θ = 2.8–39.1° |
c = 7.8579 (3) Å | µ = 5.01 mm−1 |
β = 113.205 (4)° | T = 123 K |
V = 1029.27 (6) Å3 | Block, colorless |
Z = 2 | 0.20 × 0.05 × 0.05 mm |
Oxford-Diffraction Xcalibur3 diffractometer | 5731 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 4330 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.030 |
Detector resolution: 16.0238 pixels mm-1 | θmax = 39.2°, θmin = 3.0° |
phi– and ω–rotation scans | h = −12→13 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | k = −34→30 |
Tmin = 0.602, Tmax = 1.000 | l = −13→13 |
30418 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.020 | All H-atom parameters refined |
wR(F2) = 0.046 | w = 1/[σ2(Fo2) + (0.0215P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.99 | (Δ/σ)max = 0.002 |
5731 reflections | Δρmax = 1.04 e Å−3 |
167 parameters | Δρmin = −0.93 e Å−3 |
0 restraints | Extinction correction: SHELXL2016 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00277 (14) |
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 | ||
SN1 | 0.500000 | 0.000000 | 0.500000 | 0.01140 (3) | |
F1 | 0.71015 (17) | 0.04893 (6) | 0.45645 (18) | 0.0254 (3) | |
F2 | 0.31983 (17) | 0.07728 (6) | 0.39037 (17) | 0.0232 (2) | |
F3 | 0.58561 (19) | 0.04104 (7) | 0.74794 (16) | 0.0274 (3) | |
AG1 | 0.16018 (2) | 0.12778 (2) | 0.95234 (2) | 0.01661 (3) | |
N1 | −0.1364 (2) | 0.16467 (9) | 0.8813 (2) | 0.0179 (3) | |
H1A | −0.170 (4) | 0.1789 (14) | 0.968 (4) | 0.029 (7)* | |
H1B | −0.171 (4) | 0.2005 (14) | 0.805 (4) | 0.028 (7)* | |
H1C | −0.222 (5) | 0.1286 (19) | 0.805 (5) | 0.070 (11)* | |
N2 | 0.4708 (2) | 0.10144 (9) | 1.0373 (2) | 0.0175 (3) | |
H2A | 0.509 (4) | 0.0701 (13) | 1.131 (3) | 0.021 (6)* | |
H2B | 0.485 (4) | 0.0811 (15) | 0.935 (4) | 0.041 (8)* | |
H2C | 0.557 (5) | 0.1316 (16) | 1.084 (4) | 0.044 (9)* | |
N3 | 0.0911 (3) | 0.00306 (10) | 0.8291 (3) | 0.0277 (4) | |
H3A | −0.031 (5) | −0.0050 (15) | 0.751 (5) | 0.046 (9)* | |
H3B | 0.149 (5) | −0.0181 (16) | 0.920 (5) | 0.043 (9)* | |
H3C | 0.133 (5) | −0.0059 (15) | 0.737 (4) | 0.043 (9)* | |
AG2 | 0.23394 (2) | 0.22258 (2) | 0.67497 (2) | 0.01676 (3) | |
N4 | 0.0292 (3) | 0.15407 (9) | 0.4859 (2) | 0.0196 (3) | |
H4A | 0.111 (4) | 0.1257 (14) | 0.459 (4) | 0.033 (7)* | |
H4B | −0.052 (4) | 0.1757 (14) | 0.396 (4) | 0.034 (7)* | |
H4C | −0.034 (4) | 0.1288 (15) | 0.520 (4) | 0.033 (8)* | |
N5 | 0.4733 (2) | 0.28292 (9) | 0.8539 (2) | 0.0167 (3) | |
H5A | 0.543 (4) | 0.2617 (14) | 0.973 (4) | 0.033 (7)* | |
H5B | 0.562 (4) | 0.2883 (12) | 0.793 (3) | 0.020 (6)* | |
H5C | 0.439 (5) | 0.3248 (17) | 0.891 (4) | 0.052 (9)* | |
F4 | 0.74284 (16) | 0.21290 (6) | 1.16824 (14) | 0.0177 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
SN1 | 0.01283 (6) | 0.01077 (7) | 0.01170 (7) | −0.00057 (5) | 0.00600 (5) | −0.00041 (5) |
F1 | 0.0194 (5) | 0.0291 (7) | 0.0314 (6) | −0.0056 (5) | 0.0139 (5) | 0.0066 (5) |
F2 | 0.0207 (5) | 0.0175 (5) | 0.0319 (6) | 0.0053 (4) | 0.0110 (5) | 0.0065 (5) |
F3 | 0.0329 (6) | 0.0314 (7) | 0.0179 (5) | −0.0038 (5) | 0.0098 (5) | −0.0095 (5) |
AG1 | 0.01565 (5) | 0.01867 (7) | 0.01611 (6) | 0.00126 (5) | 0.00689 (4) | 0.00184 (5) |
N1 | 0.0179 (7) | 0.0166 (7) | 0.0183 (7) | 0.0021 (6) | 0.0061 (6) | 0.0005 (6) |
N2 | 0.0175 (6) | 0.0178 (7) | 0.0160 (7) | 0.0000 (6) | 0.0053 (5) | −0.0007 (6) |
N3 | 0.0206 (8) | 0.0236 (9) | 0.0346 (10) | 0.0001 (7) | 0.0063 (8) | −0.0068 (8) |
AG2 | 0.01614 (6) | 0.01801 (7) | 0.01510 (6) | −0.00111 (5) | 0.00505 (4) | 0.00066 (4) |
N4 | 0.0184 (7) | 0.0174 (8) | 0.0194 (7) | −0.0010 (6) | 0.0035 (6) | 0.0012 (6) |
N5 | 0.0169 (6) | 0.0173 (7) | 0.0161 (7) | 0.0003 (5) | 0.0066 (5) | 0.0011 (5) |
F4 | 0.0176 (5) | 0.0200 (5) | 0.0143 (5) | −0.0003 (4) | 0.0051 (4) | −0.0015 (4) |
Sn1—F1i | 1.9518 (11) | N2—H2A | 0.91 (3) |
Sn1—F1 | 1.9518 (11) | N2—H2B | 0.94 (3) |
Sn1—F2 | 1.9617 (11) | N2—H2C | 0.83 (3) |
Sn1—F2i | 1.9617 (11) | N3—H3A | 0.88 (3) |
Sn1—F3i | 1.9655 (11) | N3—H3B | 0.79 (3) |
Sn1—F3 | 1.9656 (11) | N3—H3C | 0.91 (3) |
Ag1—N1 | 2.1434 (16) | Ag2—N4 | 2.1160 (16) |
Ag1—N2 | 2.1662 (16) | Ag2—N5 | 2.1183 (16) |
Ag1—N3 | 2.5870 (19) | N4—H4A | 0.90 (3) |
Ag1—Ag2 | 3.0611 (2) | N4—H4B | 0.84 (3) |
Ag1—Ag2ii | 3.3283 (2) | N4—H4C | 0.79 (3) |
N1—H1A | 0.85 (3) | N5—H5A | 0.96 (3) |
N1—H1B | 0.89 (3) | N5—H5B | 0.95 (3) |
N1—H1C | 0.98 (4) | N5—H5C | 0.93 (3) |
F1i—Sn1—F1 | 180.0 | Ag1—N2—H2A | 110.8 (15) |
F1i—Sn1—F2 | 90.56 (5) | Ag1—N2—H2B | 107.2 (17) |
F1—Sn1—F2 | 89.44 (5) | H2A—N2—H2B | 108 (2) |
F1i—Sn1—F2i | 89.44 (5) | Ag1—N2—H2C | 119 (2) |
F1—Sn1—F2i | 90.56 (5) | H2A—N2—H2C | 100 (2) |
F2—Sn1—F2i | 180.0 | H2B—N2—H2C | 111 (3) |
F1i—Sn1—F3i | 90.58 (6) | Ag1—N3—H3A | 115 (2) |
F1—Sn1—F3i | 89.42 (6) | Ag1—N3—H3B | 101 (2) |
F2—Sn1—F3i | 88.80 (5) | H3A—N3—H3B | 126 (3) |
F2i—Sn1—F3i | 91.19 (5) | Ag1—N3—H3C | 113.7 (19) |
F1i—Sn1—F3 | 89.42 (6) | H3A—N3—H3C | 89 (3) |
F1—Sn1—F3 | 90.58 (6) | H3B—N3—H3C | 113 (3) |
F2—Sn1—F3 | 91.19 (5) | N4—Ag2—N5 | 170.93 (7) |
F2i—Sn1—F3 | 88.81 (5) | N4—Ag2—Ag1 | 81.11 (5) |
F3i—Sn1—F3 | 180.0 | N5—Ag2—Ag1 | 101.15 (5) |
N1—Ag1—N2 | 173.74 (7) | N4—Ag2—Ag1iii | 104.96 (5) |
N1—Ag1—N3 | 100.82 (6) | N5—Ag2—Ag1iii | 77.58 (4) |
N2—Ag1—N3 | 85.44 (6) | Ag1—Ag2—Ag1iii | 149.685 (7) |
N1—Ag1—Ag2 | 93.35 (5) | Ag2—N4—H4A | 101.3 (17) |
N2—Ag1—Ag2 | 84.44 (5) | Ag2—N4—H4B | 110.4 (19) |
N3—Ag1—Ag2 | 111.20 (6) | H4A—N4—H4B | 115 (3) |
N1—Ag1—Ag2ii | 77.42 (5) | Ag2—N4—H4C | 120 (2) |
N2—Ag1—Ag2ii | 96.40 (5) | H4A—N4—H4C | 104 (3) |
N3—Ag1—Ag2ii | 169.75 (6) | H4B—N4—H4C | 107 (3) |
Ag2—Ag1—Ag2ii | 79.041 (4) | Ag2—N5—H5A | 113.0 (16) |
Ag1—N1—H1A | 118.6 (17) | Ag2—N5—H5B | 106.2 (14) |
Ag1—N1—H1B | 115.3 (18) | H5A—N5—H5B | 109 (2) |
H1A—N1—H1B | 101 (2) | Ag2—N5—H5C | 115.7 (19) |
Ag1—N1—H1C | 105 (2) | H5A—N5—H5C | 100 (2) |
H1A—N1—H1C | 114 (3) | H5B—N5—H5C | 112 (2) |
H1B—N1—H1C | 102 (3) |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x, −y+1/2, z+1/2; (iii) x, −y+1/2, z−1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···F4iv | 0.85 (3) | 2.03 (3) | 2.884 (2) | 178 (2) |
N1—H1B···F4v | 0.89 (3) | 1.96 (3) | 2.844 (2) | 171 (3) |
N1—H1C···F3iv | 0.98 (4) | 2.14 (4) | 3.057 (2) | 156 (3) |
N2—H2A···F1vi | 0.91 (3) | 2.43 (3) | 3.227 (2) | 146 (2) |
N2—H2A···F3vii | 0.91 (3) | 2.56 (3) | 3.354 (2) | 145.4 (19) |
N2—H2B···F3 | 0.94 (3) | 2.04 (3) | 2.961 (2) | 167 (3) |
N2—H2C···F4 | 0.83 (3) | 2.02 (3) | 2.849 (2) | 172 (3) |
N3—H3A···F1iv | 0.88 (3) | 2.57 (3) | 3.274 (2) | 138 (3) |
N3—H3A···F2viii | 0.88 (3) | 2.42 (3) | 3.223 (2) | 153 (3) |
N3—H3B···F3vii | 0.79 (3) | 2.61 (3) | 3.345 (3) | 157 (3) |
N3—H3C···F1i | 0.91 (3) | 2.39 (3) | 3.279 (3) | 167 (3) |
N4—H4A···F2 | 0.90 (3) | 2.04 (3) | 2.930 (2) | 170 (2) |
N4—H4B···F4ix | 0.84 (3) | 1.97 (3) | 2.7955 (19) | 171 (3) |
N4—H4C···F1iv | 0.79 (3) | 2.33 (3) | 3.045 (2) | 151 (3) |
N5—H5A···F4 | 0.96 (3) | 1.90 (3) | 2.8305 (19) | 160 (3) |
N5—H5B···F4iii | 0.95 (3) | 1.93 (3) | 2.882 (2) | 173 (2) |
N5—H5C···F2ii | 0.93 (3) | 2.09 (3) | 2.999 (2) | 163 (3) |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x, −y+1/2, z+1/2; (iii) x, −y+1/2, z−1/2; (iv) x−1, y, z; (v) x−1, −y+1/2, z−1/2; (vi) x, y, z+1; (vii) −x+1, −y, −z+2; (viii) −x, −y, −z+1; (ix) x−1, y, z−1. |
Acknowledgements
FK thanks the DFG for a Heisenberg Professorship and Dr Matthias Conrad for helpful discussions.
References
Brandenburg, K. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Hübschle, C. B., Sheldrick, G. M. & Dittrich, B. (2011). J. Appl. Cryst. 44, 1281–1284. Web of Science CrossRef IUCr Journals Google Scholar
Jansen, M. (1987). Angew. Chem. Int. Ed. Engl. 26, 1098–1110. CrossRef Web of Science Google Scholar
Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England. Google Scholar
Pyykkö, P. (1997). Chem. Rev. 97, 597–636. CrossRef PubMed Web of Science Google Scholar
Pyykkö, P. (2004). Angew. Chem. Int. Ed. 43, 4412–4456. Google Scholar
Pyykkö, P. & Mendizabal, F. (1997). Chem. Eur. J. 3, 1458–1465. Google Scholar
Pyykkö, P., Runeberg, N. & Mendizabal, F. (1997). Chem. Eur. J. 3, 1451–1457. Google Scholar
Pyykkö, P. & Zhao, Y. (1991). Angew. Chem. Int. Ed. Engl. 30, 604–605. Google Scholar
Scherbaum, F., Grohmann, A., Huber, B., Krüger, C. & Schmidbaur, H. (1988). Angew. Chem. Int. Ed. Engl. 27, 1544–1546. CSD CrossRef Google Scholar
Schmidbaur, H. (1995). Chem. Soc. Rev. 24, 391–400. CrossRef CAS Web of Science Google Scholar
Schmidbaur, H. & Schier, A. (2012). Chem. Soc. Rev. 41, 370–412. Web of Science CrossRef CAS PubMed Google Scholar
Schmidbaur, H. & Schier, A. (2015). Angew. Chem. Int. Ed. 54, 746–784. Web of Science CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Woidy, P., Karttunen, A. J., Widenmeyer, M., Niewa, R. & Kraus, F. (2015). Chem. Eur. J. 21, 3290–3303. CrossRef CAS 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.