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ISSN: 2056-9890

Tris(1,2-di­amino­ethane)­nickel(II) hexa­fluoridosilicate

aDepartment of Inorganic Chemistry, Institute of Chemistry, P. J. Šafárik University, Moyzesova 11, 041 54 Košice, Slovakia, and bDipartimento di Chimica Generale ed Inorganica, Universitá di Parma, Viale della Scienze, 43124 Parma, Italy
*Correspondence e-mail: jaroslava.hanikova@student.upjs.sk

(Received 9 September 2010; accepted 14 October 2010; online 23 October 2010)

The ionic title complex, [Ni(C2H8N2)3](SiF6), is built up of [Ni(en)3]2+ complex cations (en = 1,2-diamino­ethane) and hexa­fluoridosilicate anions. Single crystals of the title complex were isolated from an aqueous–ethano­lic Ni2+en–SiF62− system. The Ni(II) and Si atoms are each located on a special position with site symmetry 3.2. The Ni(II) atom coordination sphere is octa­hedrally deformed, being coordinated by three chelating diamine ligands with an Ni—N distance of 2.1233 (18) Å. The crystal packing of the respective ions corresponds to the structure type of the hexa­gonal form of BN. Beside ionic forces, the packing is governed by N—H⋯F hydrogen bonds, which lead to the formation of hydro­phobic channels running along the 63 screw axis. The structure was refined as an inversion twin [0.49 (3): 0.51 (3)].

Related literature

For the hexa­fluoridosilicate anion acting as simple counter-ion, see: Li et al. (2009[Li, Y., Shi, Q., Slawin, A. M. Z., Woollins, J. D. & Dong, J. (2009). Acta Cryst. E65, m1522.]). For two nickel(II) complexes containing the hexa­fluoridosilicate anion as counter-ion, see: Spek et al. (1988[Spek, A. L., Duisenberg, A. J. M., Bouwman, E., Driessen, W. L. & Reedijk, J. (1988). Acta Cryst. C44, 1569-1572.]); Wu et al. (2008[Wu, L.-P., Zhao, S.-M., Zhang, G.-F. & Ng, S. W. (2008). Acta Cryst. E64, m802.]). For complexes containing the [Ni(en)3]2+ complex cation and hexa­fluorido-type anions, see: Pan et al. (2005[Pan, Q.-H., Li, J.-Y., Yu, J.-H., Wang, Y., Fang, Q.-R. & Xu, R.-R. (2005). Gaodeng Xuexiao Huaxue Xuebao, 26, 2199-2200.]); Ribas et al. (1998[Ribas, J., Monfort, M., Resino, I., Ghosh, B. K., Solans, X. & Font-Bardia, M. (1998). Polyhedron, 17, 1735-1739.]); James et al. (1998[James, M., Kawaguchi, H. & Tatsumi, K. (1998). Polyhedron, 17, 1571-1577.]); Contakes et al. (2000[Contakes, S. M., Klausmeyer, K. K. & Rauchfuss, T. B. (2000). Inorg. Chem. 39, 2069-2075.]).

[Scheme 1]

Experimental

Crystal data
  • [Ni(C2H8N2)3](SiF6)

  • Mr = 381.11

  • Hexagonal, P 63 22

  • a = 9.1670 (9) Å

  • c = 9.763 (1) Å

  • V = 710.51 (12) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.52 mm−1

  • T = 291 K

  • 0.42 × 0.21 × 0.15 mm

Data collection
  • Oxford Diffraction Xcalibur diffractometer with Sapphire2 detector

  • Absorption correction: numerical [Clark & Reid (1995[Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897.]) in CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.])] Tmin = 0.834, Tmax = 0.859

  • 8628 measured reflections

  • 554 independent reflections

  • 489 reflections with I > 2σ(I)

  • Rint = 0.050

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.064

  • S = 1.07

  • 554 reflections

  • 33 parameters

  • H-atom parameters constrained

  • Δρmax = 0.68 e Å−3

  • Δρmin = −0.19 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 89 Friedel pairs

  • Flack parameter: 0.49 (3)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯F1i 0.90 2.30 3.137 (2) 154
N1—H1⋯F1ii 0.90 2.48 3.235 (2) 142
N1—H2⋯F1iii 0.90 2.25 3.137 (2) 167
Symmetry codes: (i) y, x, -z; (ii) -x+1, -x+y+1, -z; (iii) -x+y+1, -x+1, z.

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Crystal Impact, 2007[Crystal Impact (2007). DIAMOND. Crystal Impact, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The crystal structure of the title complex is ionic and is built up of [Ni(en)3]2+ complex cations and SiF62- anions, as shown in Fig. 1. The NiII atom (site symmetry 32) in the [Ni(en)3]2+ complex cation has a slightly deformed octahedral coordination sphere, being coordinated by six nitrogen atoms from three chelate bonded en ligands.

As the studied single-crystal was an inversion twin [ratio of the two domains was 0.49 (3):0.51 (3)] both Λδδδ and Δλλλ configurations were present in the crystal. In the isostructural [Zn(en))3]SiF6 complex the cations exhibit Λδδδ absolute configuration (Li et al., 2009). The Ni—N bond lengths of 2.1234 (18) Å (6 ×) corresponds well to the value of 2.1318 (2) Å found in the analogous hexafluoridogermanate complex [Ni(en)3]GeF6 (Pan et al., 2005). The positive charge of the complex cation is compensated for by the non-coordinated SiF62- anion, that exhibits almost ideal octahedral symmetry. The Si atom is located on the 3-fold axis (site symmetry 32). The Si—F bond length of 1.681 (2) Å (6 ×) is in line with the value of 1.6942 (15) Å found in [Zn(en)3]SiF6 (Li et al., 2009).

In the crystal the packing of the respective ions corresponds to the hexagonal structure of BN, with a Ni···Si distance of 5.2927 (4) Å within the hexagonal plane and a Ni···Si distance of 4.8815 (5) Å between the planes (Fig. 2). To the packing forces contribute also N—H···F type hydrogen bonds with N···F distances in the range 3.137 (2) - 3.235 (2) Å (Table 1, Fig. 3). Some of the hydrogen bonds are three-centered with two fluorido acceptors. The observed geometric parameters associated with the hydrogen bonds correspond to those in Zn(en))3]SiF6 (Li et al., 2009) where the N···F distances range from 3.113 (3) - 3.239 (3) Å. The hydrogen bonding leads to the formation of hydrophobic channels running along the 63 screw axis (Fig. 4a and 4 b), as was already observed in the GeF6 analog (Pan et al., 2005).

Related literature top

For the hexafluoridosilicate anion acting as simple counter-ion, see: Li et al. (2009). For two nickel(II) complexes containing the hexafluoridosilicate anion as counter-ion, see: Spek et al. (1988); Wu et al. (2008). For complexes containing the [Ni(en)3]2+ complex cation and hexafluorido-type anions, see: Pan et al. (2005); Ribas et al. (1998); James et al. (1998); Contakes et al. (2000).

Experimental top

To a solution of 0.24 g of NiCl2.6H2O (1 mmol) in 10 cm3 of water:ethanol mixture (1:1 in vol) wre added successively 0.27 cm3 of 1,2-diaminoethane (en) (4 mmol) and 0.18 g of (NH4)SiF6 (1 mmol), dissolved in 10 cm3 of water:ethanol mixture (1:1 / v:v), under constant stirring. The dark pink solution that formed was filtered and left aside for crystallization at RT. Within a few days light-pink prisms were formed. They were collected by filtration and subsequently recrystallized from a water:ethanol mixture to give crystals suitable for X-ray diffraction analysis. Anal. [%], calculated for Ni1C6N6H24Si1F6: C, 18.92; H, 6.35; N, 22.05. Found: C, 18.97; H, 5.76; N, 14.55. IR (KBr pellets, FT—IR Avatar 330 (ThermoNicolet), cm-1): 3300m; 3170m; 2954m; 2925m; 2887m; 1598 s; 1456 s; 1385w; 1370w; 1125 s; 1064 s, 717 s; 500 s; 478m. Thermal Analysis (TA Instrument, air atmosphere): the complex was thermally stable up to 501 K and decomposed in one step in the temperature range 501 - 693 K.

Refinement top

The structure was refined as an inversion twin [0.49 (3): 0.51 (3)]. All the H atoms were included in calculated positions and treated as riding atoms: N—H = 0.90 Å, C—H = 0.97 Å, with Uiso(H) = 1.2Ueq(parent N– or C-atom).

Structure description top

The crystal structure of the title complex is ionic and is built up of [Ni(en)3]2+ complex cations and SiF62- anions, as shown in Fig. 1. The NiII atom (site symmetry 32) in the [Ni(en)3]2+ complex cation has a slightly deformed octahedral coordination sphere, being coordinated by six nitrogen atoms from three chelate bonded en ligands.

As the studied single-crystal was an inversion twin [ratio of the two domains was 0.49 (3):0.51 (3)] both Λδδδ and Δλλλ configurations were present in the crystal. In the isostructural [Zn(en))3]SiF6 complex the cations exhibit Λδδδ absolute configuration (Li et al., 2009). The Ni—N bond lengths of 2.1234 (18) Å (6 ×) corresponds well to the value of 2.1318 (2) Å found in the analogous hexafluoridogermanate complex [Ni(en)3]GeF6 (Pan et al., 2005). The positive charge of the complex cation is compensated for by the non-coordinated SiF62- anion, that exhibits almost ideal octahedral symmetry. The Si atom is located on the 3-fold axis (site symmetry 32). The Si—F bond length of 1.681 (2) Å (6 ×) is in line with the value of 1.6942 (15) Å found in [Zn(en)3]SiF6 (Li et al., 2009).

In the crystal the packing of the respective ions corresponds to the hexagonal structure of BN, with a Ni···Si distance of 5.2927 (4) Å within the hexagonal plane and a Ni···Si distance of 4.8815 (5) Å between the planes (Fig. 2). To the packing forces contribute also N—H···F type hydrogen bonds with N···F distances in the range 3.137 (2) - 3.235 (2) Å (Table 1, Fig. 3). Some of the hydrogen bonds are three-centered with two fluorido acceptors. The observed geometric parameters associated with the hydrogen bonds correspond to those in Zn(en))3]SiF6 (Li et al., 2009) where the N···F distances range from 3.113 (3) - 3.239 (3) Å. The hydrogen bonding leads to the formation of hydrophobic channels running along the 63 screw axis (Fig. 4a and 4 b), as was already observed in the GeF6 analog (Pan et al., 2005).

For the hexafluoridosilicate anion acting as simple counter-ion, see: Li et al. (2009). For two nickel(II) complexes containing the hexafluoridosilicate anion as counter-ion, see: Spek et al. (1988); Wu et al. (2008). For complexes containing the [Ni(en)3]2+ complex cation and hexafluorido-type anions, see: Pan et al. (2005); Ribas et al. (1998); James et al. (1998); Contakes et al. (2000).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: 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 (Crystal Impact, 2007); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title ionic complex along with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing of the ions in the title complex leading to the hexagonal BN structure type.
[Figure 3] Fig. 3. Detailed view of the hydrogen bonding scheme (dashed lines) in the title complex. For the sake of clarity only the NH2 groups of the en ligands are shown. Symmetry codes: (i) = y, x, -z; (ii) = 1 - x, 1 - x + y, z; (iii) = 1 - x + y, 1 - x, z.
[Figure 4] Fig. 4. Formation of hydrophobic pseudo-channels inside the hydrogen bonded complex cations and anions running along the 63 screw axis: view of one channel. Hydrogen atoms bonded to the carbon atoms are omitted for the sake of clarity.
[Figure 5] Fig. 5. Formation of hydrophobic pseudo-channels inside the hydrogen bonded complex cations and anions running along the 63 screw axis: arrangement of the neighbouring channels. Hydrogen atoms bonded to the carbon atoms are omitted for the sake of clarity.
Tris(1,2-diaminoethane)nickel(II) hexafluoridosilicate top
Crystal data top
[Ni(C2H8N2)3](SiF6)Dx = 1.781 Mg m3
Mr = 381.11Mo Kα radiation, λ = 0.71069 Å
Hexagonal, P6322Cell parameters from 8628 reflections
Hall symbol: P 6c 2cθ = 2.6–27.4°
a = 9.1670 (9) ŵ = 1.52 mm1
c = 9.763 (1) ÅT = 291 K
V = 710.51 (12) Å3Prism, pink
Z = 20.42 × 0.21 × 0.15 mm
F(000) = 396
Data collection top
Oxford Diffraction Xcalibur
diffractometer with Sapphire2 detector
554 independent reflections
Radiation source: fine-focus sealed tube489 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.050
Detector resolution: 8.3438 pixels mm-1θmax = 27.4°, θmin = 2.6°
ω scansh = 1111
Absorption correction: numerical
[Clark & Reid (1995) in CrysAlis PRO (Oxford Diffraction, 2009)]
k = 1111
Tmin = 0.834, Tmax = 0.859l = 1212
8628 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.064 w = 1/[σ2(Fo2) + (0.0413P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
554 reflectionsΔρmax = 0.68 e Å3
33 parametersΔρmin = 0.19 e Å3
0 restraintsAbsolute structure: Flack (1983), 89 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.49 (3)
Crystal data top
[Ni(C2H8N2)3](SiF6)Z = 2
Mr = 381.11Mo Kα radiation
Hexagonal, P6322µ = 1.52 mm1
a = 9.1670 (9) ÅT = 291 K
c = 9.763 (1) Å0.42 × 0.21 × 0.15 mm
V = 710.51 (12) Å3
Data collection top
Oxford Diffraction Xcalibur
diffractometer with Sapphire2 detector
554 independent reflections
Absorption correction: numerical
[Clark & Reid (1995) in CrysAlis PRO (Oxford Diffraction, 2009)]
489 reflections with I > 2σ(I)
Tmin = 0.834, Tmax = 0.859Rint = 0.050
8628 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.064Δρmax = 0.68 e Å3
S = 1.07Δρmin = 0.19 e Å3
554 reflectionsAbsolute structure: Flack (1983), 89 Friedel pairs
33 parametersAbsolute structure parameter: 0.49 (3)
0 restraints
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Ni10.33330.66670.25000.02783 (19)
N10.3156 (2)0.4642 (2)0.13146 (17)0.0368 (4)
H10.30980.48390.04190.044*
H20.40760.45470.14490.044*
C10.1634 (3)0.3071 (2)0.1729 (2)0.0432 (5)
H50.17320.21070.14550.052*
H60.06510.29920.12840.052*
Si10.66670.33330.25000.0267 (3)
F10.51790 (19)0.18375 (19)0.14983 (14)0.0550 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0286 (2)0.0286 (2)0.0262 (3)0.01432 (11)0.0000.000
N10.0401 (10)0.0429 (11)0.0319 (9)0.0241 (9)0.0020 (8)0.0013 (8)
C10.0428 (16)0.0339 (10)0.0489 (12)0.0162 (13)0.0016 (11)0.0079 (8)
Si10.0270 (3)0.0270 (3)0.0262 (5)0.01349 (17)0.0000.000
F10.0521 (8)0.0495 (8)0.0489 (8)0.0145 (6)0.0110 (7)0.0086 (7)
Geometric parameters (Å, º) top
Ni1—N1i2.1233 (18)C1—C1iv1.515 (4)
Ni1—N1ii2.1233 (18)C1—H50.9700
Ni1—N1iii2.1233 (18)C1—H60.9700
Ni1—N1iv2.1233 (18)Si1—F1vi1.6812 (14)
Ni1—N12.1233 (18)Si1—F1vii1.6812 (14)
Ni1—N1v2.1233 (18)Si1—F11.6812 (14)
N1—C11.475 (2)Si1—F1v1.6812 (14)
N1—H10.9000Si1—F1viii1.6812 (14)
N1—H20.9000Si1—F1ix1.6812 (14)
N1i—Ni1—N1ii81.62 (9)N1—C1—C1iv109.08 (16)
N1i—Ni1—N1iii93.12 (7)N1—C1—H5109.9
N1ii—Ni1—N1iii92.62 (10)C1iv—C1—H5109.9
N1i—Ni1—N1iv92.62 (10)N1—C1—H6109.9
N1ii—Ni1—N1iv93.12 (7)C1iv—C1—H6109.9
N1iii—Ni1—N1iv172.42 (9)H5—C1—H6108.3
N1i—Ni1—N193.12 (7)F1vi—Si1—F1vii90.75 (10)
N1ii—Ni1—N1172.42 (9)F1vi—Si1—F190.12 (10)
N1iii—Ni1—N193.12 (6)F1vii—Si1—F189.57 (7)
N1iv—Ni1—N181.62 (9)F1vi—Si1—F1v89.57 (7)
N1i—Ni1—N1v172.42 (9)F1vii—Si1—F1v90.12 (10)
N1ii—Ni1—N1v93.12 (7)F1—Si1—F1v179.56 (10)
N1iii—Ni1—N1v81.62 (9)F1vi—Si1—F1viii89.57 (7)
N1iv—Ni1—N1v93.12 (6)F1vii—Si1—F1viii179.56 (10)
N1—Ni1—N1v92.62 (10)F1—Si1—F1viii90.75 (10)
C1—N1—Ni1108.97 (13)F1v—Si1—F1viii89.57 (7)
C1—N1—H1109.9F1vi—Si1—F1ix179.56 (10)
Ni1—N1—H1109.9F1vii—Si1—F1ix89.57 (7)
C1—N1—H2109.9F1—Si1—F1ix89.57 (7)
Ni1—N1—H2109.9F1v—Si1—F1ix90.75 (10)
H1—N1—H2108.3F1viii—Si1—F1ix90.12 (10)
N1i—Ni1—N1—C178.08 (18)N1v—Ni1—N1—C1106.88 (16)
N1iii—Ni1—N1—C1171.38 (15)Ni1—N1—C1—C1iv39.4 (3)
N1iv—Ni1—N1—C114.11 (12)
Symmetry codes: (i) x+y, x+1, z; (ii) x, xy+1, z+1/2; (iii) y+1, xy+1, z; (iv) x+y, y, z+1/2; (v) y+1, x+1, z+1/2; (vi) x+y+1, y, z+1/2; (vii) y+1, xy, z; (viii) x, xy, z+1/2; (ix) x+y+1, x+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···F1x0.902.303.137 (2)154
N1—H1···F1xi0.902.483.235 (2)142
N1—H2···F1ix0.902.253.137 (2)167
Symmetry codes: (ix) x+y+1, x+1, z; (x) y, x, z; (xi) x+1, x+y+1, z.

Experimental details

Crystal data
Chemical formula[Ni(C2H8N2)3](SiF6)
Mr381.11
Crystal system, space groupHexagonal, P6322
Temperature (K)291
a, c (Å)9.1670 (9), 9.763 (1)
V3)710.51 (12)
Z2
Radiation typeMo Kα
µ (mm1)1.52
Crystal size (mm)0.42 × 0.21 × 0.15
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer with Sapphire2 detector
Absorption correctionNumerical
[Clark & Reid (1995) in CrysAlis PRO (Oxford Diffraction, 2009)]
Tmin, Tmax0.834, 0.859
No. of measured, independent and
observed [I > 2σ(I)] reflections
8628, 554, 489
Rint0.050
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.064, 1.07
No. of reflections554
No. of parameters33
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.68, 0.19
Absolute structureFlack (1983), 89 Friedel pairs
Absolute structure parameter0.49 (3)

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Crystal Impact, 2007).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···F1i0.902.303.137 (2)154
N1—H1···F1ii0.902.483.235 (2)142
N1—H2···F1iii0.902.253.137 (2)167
Symmetry codes: (i) y, x, z; (ii) x+1, x+y+1, z; (iii) x+y+1, x+1, z.
 

Acknowledgements

This work was supported by the Slovak grant agencies VEGA (grant 1/0089/09) and APVV (contract Nos. APVV-VVCE-0058–07 and APVV-0006–07). Support from P. J. Šafárik University (VVGS PF 19/2010/CH) is also gratefully acknowledged. We thank student M. Adam for help with the experimental work.

References

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