Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270107015843/gg3082sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107015843/gg3082Isup2.hkl |
CCDC reference: 652485
For related literature, see: Ahrland et al. (1985, 1993); Allen (2002); Annibale et al. (2004); Braunstein & Clark (1973); Friedrichs & Jones (1999); Hayoun et al. (2006); Humphrey et al. (2004); Orpen et al. (1994); Pyykkö (1997); Schneider et al. (2005).
[Pt(terpy)Cl]Cl (Annibale et al., 2004) and [Et4N][AuBr2] (Braunstein & Clark, 1973) were prepared according to literature procedures. For the synthesis of [Pt(terpy)I]I, [Pt(terpy)Cl]Cl (0.0504 g) was dissolved in water (5 ml) and to this was added a 0.4196 g portion of KI dissolved in water (3 ml). A thick bright-fuschia precipitate formed, which faded to an apricot color after 10 min. The solution was left to stand overnight, resulting in a uniform dark-canary-yellow precipitate, which was filtered off and washed with cold water for an 85.8% yield. Analysis calculated for C15H11N3Pt1I2: C 26.41, H 1.63, N 6.16%; found: C 26.54, H 1.58, N 6.21%. For the synthesis of [Et4N][AuI2], a 0.3312 g portion of [Et4N][AuBr2] was dissolved in absolute ethanol (4 ml) and to this solution was added a 0.3473 g portion of [Et4N]I dissolved in absolute ethanol (4 ml); the solution was heated to 313 K for 1 min then left to cool to room temperature. Upon heating the solution turned a clear brown color and several minutes after cooling a dark-brown precipitate formed in 68% yield. For the synthesis of [Pt(terpy)I][AuI2], a 0.0525 g portion of [Et4N][AuI2] was dissolved in absolute ethanol (15 ml) to produce a clear light-brown solution. This was added to a partially dissolved solution of 0.0625 g of [Pt(terpy)I]I in absolute ethanol (415 ml), which turned fuschia-orange and opaque and was stirred for 5 min to give a 83% yield of (I). X-ray quality crystals were grown from dimethylsulfoxide and vapor diffused with diethyl ether.
Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: Cameron (Watkin et al., 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2007).
[PtI(C15H11N3)][AuI2] | Z = 2 |
Mr = 1006.02 | F(000) = 876 |
Triclinic, P1 | Dx = 3.580 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.7124 (6) Å | Cell parameters from 8611 reflections |
b = 9.0668 (6) Å | θ = 2.4–28.2° |
c = 11.9860 (8) Å | µ = 20.30 mm−1 |
α = 84.085 (1)° | T = 100 K |
β = 82.476 (1)° | Block, red |
γ = 87.554 (1)° | 0.18 × 0.13 × 0.10 mm |
V = 933.26 (11) Å3 |
Bruker SMART CCD area-detector diffractometer | 4155 independent reflections |
Radiation source: fine-focus sealed tube | 4099 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ϕ and ω scans | θmax = 28.2°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) | h = −10→11 |
Tmin = 0.121, Tmax = 0.236 | k = −12→11 |
9589 measured reflections | l = −15→15 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.026 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.065 | H-atom parameters constrained |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0212P)2 + 7.9416P] where P = (Fo2 + 2Fc2)/3 |
4155 reflections | (Δ/σ)max = 0.029 |
208 parameters | Δρmax = 1.43 e Å−3 |
0 restraints | Δρmin = −1.81 e Å−3 |
[PtI(C15H11N3)][AuI2] | γ = 87.554 (1)° |
Mr = 1006.02 | V = 933.26 (11) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.7124 (6) Å | Mo Kα radiation |
b = 9.0668 (6) Å | µ = 20.30 mm−1 |
c = 11.9860 (8) Å | T = 100 K |
α = 84.085 (1)° | 0.18 × 0.13 × 0.10 mm |
β = 82.476 (1)° |
Bruker SMART CCD area-detector diffractometer | 4155 independent reflections |
Absorption correction: multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) | 4099 reflections with I > 2σ(I) |
Tmin = 0.121, Tmax = 0.236 | Rint = 0.027 |
9589 measured reflections |
R[F2 > 2σ(F2)] = 0.026 | 0 restraints |
wR(F2) = 0.065 | H-atom parameters constrained |
S = 1.09 | Δρmax = 1.43 e Å−3 |
4155 reflections | Δρmin = −1.81 e Å−3 |
208 parameters |
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 | ||
Pt1 | 0.60794 (2) | 0.39920 (2) | 0.396570 (19) | 0.01151 (7) | |
Au1 | 0.57885 (3) | 0.12408 (3) | 0.13364 (2) | 0.01798 (7) | |
I1 | 0.81674 (5) | 0.33353 (5) | 0.53068 (4) | 0.01814 (10) | |
I2 | 0.84371 (5) | 0.23924 (5) | 0.12460 (4) | 0.02055 (10) | |
I3 | 0.31905 (5) | −0.00343 (5) | 0.15949 (4) | 0.02039 (10) | |
N1 | 0.4458 (6) | 0.2521 (6) | 0.4689 (4) | 0.0140 (10) | |
N2 | 0.4555 (6) | 0.4389 (6) | 0.2909 (4) | 0.0126 (10) | |
N3 | 0.7185 (6) | 0.5601 (6) | 0.2892 (4) | 0.0146 (10) | |
C1 | 0.4489 (7) | 0.1597 (7) | 0.5642 (6) | 0.0170 (12) | |
H1A | 0.5352 | 0.1591 | 0.6052 | 0.020* | |
C2 | 0.3284 (8) | 0.0655 (7) | 0.6034 (6) | 0.0204 (13) | |
H2A | 0.3323 | 0.0019 | 0.6712 | 0.024* | |
C3 | 0.2031 (8) | 0.0636 (8) | 0.5448 (6) | 0.0233 (14) | |
H3A | 0.1199 | −0.0005 | 0.5714 | 0.028* | |
C4 | 0.2009 (7) | 0.1572 (8) | 0.4463 (6) | 0.0185 (13) | |
H4A | 0.1165 | 0.1566 | 0.4036 | 0.022* | |
C5 | 0.3221 (7) | 0.2519 (7) | 0.4099 (5) | 0.0164 (12) | |
C6 | 0.3274 (7) | 0.3576 (7) | 0.3083 (6) | 0.0158 (12) | |
C7 | 0.2193 (7) | 0.3828 (7) | 0.2330 (6) | 0.0189 (13) | |
H7A | 0.1272 | 0.3278 | 0.2437 | 0.023* | |
C8 | 0.2474 (8) | 0.4894 (8) | 0.1414 (6) | 0.0210 (14) | |
H8A | 0.1740 | 0.5069 | 0.0891 | 0.025* | |
C9 | 0.3805 (8) | 0.5703 (8) | 0.1255 (6) | 0.0202 (13) | |
H9A | 0.3992 | 0.6428 | 0.0626 | 0.024* | |
C10 | 0.4874 (7) | 0.5440 (7) | 0.2032 (5) | 0.0160 (12) | |
C11 | 0.6362 (7) | 0.6136 (7) | 0.2018 (5) | 0.0156 (12) | |
C12 | 0.6926 (8) | 0.7246 (8) | 0.1211 (5) | 0.0193 (13) | |
H12A | 0.6335 | 0.7614 | 0.0624 | 0.023* | |
C13 | 0.8359 (8) | 0.7819 (7) | 0.1264 (6) | 0.0230 (14) | |
H13A | 0.8762 | 0.8579 | 0.0711 | 0.028* | |
C14 | 0.9201 (8) | 0.7276 (7) | 0.2129 (6) | 0.0225 (14) | |
H14A | 1.0193 | 0.7646 | 0.2173 | 0.027* | |
C15 | 0.8563 (7) | 0.6173 (7) | 0.2937 (6) | 0.0182 (13) | |
H15A | 0.9129 | 0.5816 | 0.3540 | 0.022* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Pt1 | 0.01076 (11) | 0.01197 (12) | 0.01223 (12) | 0.00068 (8) | −0.00447 (8) | 0.00018 (8) |
Au1 | 0.01888 (13) | 0.01848 (13) | 0.01660 (13) | 0.00238 (9) | −0.00504 (9) | 0.00047 (9) |
I1 | 0.01563 (19) | 0.0195 (2) | 0.0209 (2) | 0.00123 (15) | −0.00957 (15) | −0.00116 (16) |
I2 | 0.0195 (2) | 0.0240 (2) | 0.0188 (2) | −0.00046 (16) | −0.00487 (16) | −0.00247 (16) |
I3 | 0.0215 (2) | 0.0201 (2) | 0.0198 (2) | −0.00059 (16) | −0.00389 (16) | −0.00152 (16) |
N1 | 0.010 (2) | 0.017 (3) | 0.015 (3) | 0.0000 (19) | −0.0029 (19) | 0.000 (2) |
N2 | 0.013 (2) | 0.012 (2) | 0.012 (2) | 0.0024 (19) | −0.0035 (19) | 0.0009 (19) |
N3 | 0.018 (2) | 0.012 (2) | 0.014 (3) | 0.0030 (19) | −0.002 (2) | −0.0006 (19) |
C1 | 0.017 (3) | 0.015 (3) | 0.018 (3) | 0.005 (2) | −0.002 (2) | 0.001 (2) |
C2 | 0.025 (3) | 0.017 (3) | 0.019 (3) | 0.004 (3) | −0.002 (3) | −0.002 (3) |
C3 | 0.018 (3) | 0.027 (4) | 0.024 (4) | −0.009 (3) | 0.003 (3) | −0.001 (3) |
C4 | 0.011 (3) | 0.026 (4) | 0.020 (3) | −0.003 (2) | −0.003 (2) | −0.003 (3) |
C5 | 0.013 (3) | 0.020 (3) | 0.017 (3) | 0.002 (2) | −0.004 (2) | −0.002 (2) |
C6 | 0.012 (3) | 0.015 (3) | 0.021 (3) | −0.001 (2) | −0.004 (2) | −0.006 (2) |
C7 | 0.018 (3) | 0.014 (3) | 0.026 (3) | 0.003 (2) | −0.011 (3) | 0.003 (3) |
C8 | 0.025 (3) | 0.020 (3) | 0.021 (3) | 0.005 (3) | −0.014 (3) | −0.005 (3) |
C9 | 0.025 (3) | 0.020 (3) | 0.016 (3) | 0.006 (3) | −0.008 (3) | 0.001 (2) |
C10 | 0.018 (3) | 0.015 (3) | 0.015 (3) | 0.003 (2) | −0.003 (2) | −0.002 (2) |
C11 | 0.018 (3) | 0.013 (3) | 0.016 (3) | 0.006 (2) | −0.001 (2) | −0.003 (2) |
C12 | 0.027 (3) | 0.021 (3) | 0.009 (3) | 0.002 (3) | 0.002 (2) | −0.001 (2) |
C13 | 0.027 (3) | 0.015 (3) | 0.023 (4) | −0.002 (3) | 0.006 (3) | 0.003 (3) |
C14 | 0.019 (3) | 0.017 (3) | 0.031 (4) | −0.007 (3) | 0.002 (3) | −0.002 (3) |
C15 | 0.018 (3) | 0.015 (3) | 0.023 (3) | 0.001 (2) | −0.004 (2) | −0.004 (2) |
Pt1—N2 | 1.950 (5) | C4—H4A | 0.9500 |
Pt1—N3 | 2.030 (5) | C5—C6 | 1.467 (9) |
Pt1—N1 | 2.031 (5) | C6—C7 | 1.384 (9) |
Pt1—I1 | 2.5930 (5) | C7—C8 | 1.389 (9) |
Au1—I3 | 2.5538 (5) | C7—H7A | 0.9500 |
Au1—I2 | 2.5580 (5) | C8—C9 | 1.380 (10) |
N1—C1 | 1.348 (8) | C8—H8A | 0.9500 |
N1—C5 | 1.365 (8) | C9—C10 | 1.397 (9) |
N2—C6 | 1.345 (8) | C9—H9A | 0.9500 |
N2—C10 | 1.353 (8) | C10—C11 | 1.464 (9) |
N3—C15 | 1.338 (8) | C11—C12 | 1.381 (9) |
N3—C11 | 1.382 (8) | C12—C13 | 1.383 (10) |
C1—C2 | 1.384 (9) | C12—H12A | 0.9500 |
C1—H1A | 0.9500 | C13—C14 | 1.386 (10) |
C2—C3 | 1.375 (10) | C13—H13A | 0.9500 |
C2—H2A | 0.9500 | C14—C15 | 1.398 (9) |
C3—C4 | 1.383 (10) | C14—H14A | 0.9500 |
C3—H3A | 0.9500 | C15—H15A | 0.9500 |
C4—C5 | 1.386 (9) | ||
N2—Pt1—N3 | 80.8 (2) | N2—C6—C7 | 118.6 (6) |
N2—Pt1—N1 | 80.7 (2) | N2—C6—C5 | 112.9 (5) |
N3—Pt1—N1 | 161.5 (2) | C7—C6—C5 | 128.5 (6) |
N2—Pt1—I1 | 176.68 (15) | C6—C7—C8 | 119.1 (6) |
N3—Pt1—I1 | 99.63 (15) | C6—C7—H7A | 120.5 |
N1—Pt1—I1 | 98.90 (15) | C8—C7—H7A | 120.5 |
I3—Au1—I2 | 174.871 (17) | C9—C8—C7 | 120.8 (6) |
C1—N1—C5 | 119.3 (5) | C9—C8—H8A | 119.6 |
C1—N1—Pt1 | 127.8 (4) | C7—C8—H8A | 119.6 |
C5—N1—Pt1 | 112.9 (4) | C8—C9—C10 | 119.1 (6) |
C6—N2—C10 | 124.3 (5) | C8—C9—H9A | 120.4 |
C6—N2—Pt1 | 117.9 (4) | C10—C9—H9A | 120.4 |
C10—N2—Pt1 | 117.8 (4) | N2—C10—C9 | 118.0 (6) |
C15—N3—C11 | 118.4 (6) | N2—C10—C11 | 113.5 (5) |
C15—N3—Pt1 | 128.3 (5) | C9—C10—C11 | 128.4 (6) |
C11—N3—Pt1 | 113.3 (4) | C12—C11—N3 | 121.4 (6) |
N1—C1—C2 | 121.1 (6) | C12—C11—C10 | 123.9 (6) |
N1—C1—H1A | 119.4 | N3—C11—C10 | 114.6 (5) |
C2—C1—H1A | 119.4 | C11—C12—C13 | 119.5 (6) |
C3—C2—C1 | 120.3 (6) | C11—C12—H12A | 120.3 |
C3—C2—H2A | 119.8 | C13—C12—H12A | 120.3 |
C1—C2—H2A | 119.8 | C14—C13—C12 | 119.5 (6) |
C2—C3—C4 | 118.5 (6) | C14—C13—H13A | 120.3 |
C2—C3—H3A | 120.7 | C12—C13—H13A | 120.3 |
C4—C3—H3A | 120.7 | C13—C14—C15 | 118.7 (6) |
C3—C4—C5 | 119.9 (6) | C13—C14—H14A | 120.7 |
C3—C4—H4A | 120.0 | C15—C14—H14A | 120.7 |
C5—C4—H4A | 120.0 | N3—C15—C14 | 122.5 (6) |
N1—C5—C4 | 120.8 (6) | N3—C15—H15A | 118.8 |
N1—C5—C6 | 115.6 (5) | C14—C15—H15A | 118.8 |
C4—C5—C6 | 123.6 (6) |
Experimental details
Crystal data | |
Chemical formula | [PtI(C15H11N3)][AuI2] |
Mr | 1006.02 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 100 |
a, b, c (Å) | 8.7124 (6), 9.0668 (6), 11.9860 (8) |
α, β, γ (°) | 84.085 (1), 82.476 (1), 87.554 (1) |
V (Å3) | 933.26 (11) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 20.30 |
Crystal size (mm) | 0.18 × 0.13 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Blessing, 1995; Sheldrick, 1996) |
Tmin, Tmax | 0.121, 0.236 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9589, 4155, 4099 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.666 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.026, 0.065, 1.09 |
No. of reflections | 4155 |
No. of parameters | 208 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.43, −1.81 |
Computer programs: SMART (Bruker, 2005), SAINT (Bruker, 2005), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), Cameron (Watkin et al., 1996) and Mercury (Macrae et al., 2006), publCIF (Westrip, 2007).
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Metallophilicity has been observed as a subtle yet significant force in forming M···M contacts (Pyykkö, 1997). We are interested in making wires of sub-
millimeter length in single-crystal form with single atom-wide conducting paths in the center and have synthesized double salts of {X-platinum-2,2':6',2"-terpyridine}[AuX'n], where X is CN or Cl, X' is a halogen, and n is 2 or 4 (Hayoun et al., 2006). The title compound, (I), is closely related to the reported [Pt(terpy)Cl][AuCl2] double salt and, although the compounds differ only in the halide, this change has resulted in different crystal packing.
We report the structure of [Pt(terpy)I][AuI2], (I) (where terpy is 2,2':6',2"-terpyridine); the asymmetric unit comprises a [PtI(terpy)]+ cation and an [AuI2]- anion, as depicted in Fig. 1. A search of the Cambridge Structural Database (Version 5.28 of November 2006; Allen, 2002) for [Pt(terpy)X]+ cations (X is any halogen) revealed the chloride derivative as the only structurally characterized form of the halogenated cation. The Pt atom in (I) is in a nearly square-planar environment with an N1—Pt1—N3 angle of 161.5 (2)° and a N2—Pt1—I1 angle of 176.68 (15)°. The Pt center lies 0.004 Å from the plane defined by the pyridine N atoms (N1, N2 and N3). The Pt1—I1 distance is 2.5930 (5) Å and is comparable to the average PtII—I distance of 2.62 (5) Å (Orpen et al., 1994). The iodide ion lies 0.159 Å from the plane defined by the three N atoms, within the range of reported values seen in [Pt(terpy)Cl]+ cations, but above the average value of 0.05 (5) Å. The [PtI(terpy)]+ cations exhibit pair-wise stacking with a symmetry-related cation, [PtI(terpy)]+ at (1 - x, 1 - y, 1 - z), resulting in a Pt···Pt interaction of 3.5279 (5) Å. A weak hydrogen bond is present between the [Pt(terpy)I] and [Pt(terpy)I]i cations [symmetry code: (i) 2 - x, 1 - y, 1 - z] and the C15···I1i distance of 3.824 (7) Å (the C15—H15A···I1i angle is 140°) as depicted in Fig. 2.
The [AuI2]- anion has been observed to undergo metallophilic interactions in compounds of the form [L2Au]+·[AuI2]-. Two structurally characterized examples of [AuI2]--containing complexes exhibiting aurophilic interactions are the imidazolidine-2-thione derivative [Au(C3H6N2S)2]+·[AuI2]-, (Friedrichs & Jones, 1999) and [(tBuNC)2Au]+·[AuI2]-(I2) (Schneider et al., 2005). Aurophilic interactions were also observed in the tetrahydrothiophene salt [(C4H8S)2Au]+·[AuI2]- (Ahrland et al., 1985) and the tetrahydroselenophene salt, [(C4H8Se)2Au]+·[AuI2]- (Ahrland et al., 1993). In (I), the nearly linear [AuI2]- anion (Fig. 1) lies parallel to the a axis and exhibits an I2—Au1—I3 angle of 174.871 (17)°, consistent with previously reported values. The Au—I2 and Au1—I3 bond lengths of 2.5580 (5) Å and 2.5538 (5) Å, respectively, are also consistent with previously reported values. As shown in Fig. 2, the [AuI2]- anions stack pairwise, with short contacts between Au1 and I3 at (1 - x, -y, -z) at a distance of 3.7713 (5) Å, about inversion centers.
In Fig. 1, the [AuI2]- anions stack near the [PtI(terpy)]+ terpyridine planes, with I2 and Au1 at distances of 3.667 and 3.571 Å, respectively, above the plane defined by the three terpyridine N atoms. The shortest contact between the [PtI(terpy)]+ cation and the [AuI2]- anion is for N2 and Au1, at 3.629 (5) Å [a close contact between N3 and I2 is 3.727 (5) Å]. The shortest contact from the Pt atom in the cation to the anion is for Pt1···I2, at 3.9894 (5) Å [the Au1···Pt1 distance is 4.2546 (4) Å; Fig 2]. Although no continuous metal chain exists in (I), ···[(cation–cation)···(anion–anion)]··· units are evident, and a pairwise metallophilic interaction exists between the Pt-containing cations.
The [Cl(terpy)PtII][Cl2AuI] derivative, which crystallizes to form red, block-shaped crystals of {[Pt(terpy)Cl]2[AuCl2]}[AuCl2], has been previously characterized (Hayoun et al., 2006) and Fig. 3 shows the infinite metal chains consisting of ···Pt1···Au1···Pt1···Pt1··· contacts. An additional [AuCl2]- anion is found perpendicular to the terpyridine planes. In the chloro derivative, the Pt1···Pt1 distance is 3.453 (1) Å and the Au1···Pt1 contact is 3.268 (1) Å.
As iodine is less electronegative than chlorine, one would expect more electron density on the metal centers in (I) than in the Cl derivative; this is expected to promote metallophilic interactions in (I) (Ahrland et al., 1993). Humphrey et al. (2004) prepared (isocyanide)gold(I) halides in which the extent of metallophilicity was shown to be dependent on the nature of the halide substituent. As the I atoms are larger than the Au atom, the Au center in the [AuI2]- anion is sterically hindered from metallophilically interacting with the Pt center, which is surrounded by a rigid planar ligand environment. Space-filling diagrams of (I) and the Cl derivative are shown in Figs. 4(a) and 4(b), respectively.
Synthesis of the bromo derivative of (I) is in progress. Recrystallization of (I) from solvents other than dimethylsulfoxide is also underway, as the Cl derivative crystallized with one acetonitrile solvent molecule, and such packing may influence the metallophilic interactions.