supplementary materials


HTML versionpdf versioncif file3d viewstructure factorssupplementary materialsCIF check reportsimilar papers Open access

Acta Cryst. (2009). E65, i29    [ doi:10.1107/S1600536809009702 ]

[Cu2(HF2)(H2O)8][AlF6]·2H2O

M. Weil

Abstract top

The title compound, octaaqua(hydrogendifluorido)dicopper(II) hexafluoridoaluminate dihydrate, was obtained under hydrothermal conditions. The structure is isotypic with that of the analogous FeIII compound, [Cu2(HF2)(H2O)8][FeF6]·2H2O. The coordination sphere of the CuII atom is formed by one F and three water O atoms at short distances < 2 Å and is augmented by two additional water O atoms at significantly longer distances, leading to a considerably distorted octahedral environment. By edge-sharing, these octahedra form dimeric [Cu2(HF2)(H2O)8]3+ units that are bonded to [AlF6]3- anions (\overline{1} symmetry) and to crystal lattice water molecules via hydrogen bonds. Besides F-H...F interactions between the dimeric cationic units, O-H...F and O-H...O hydrogen bonds (both in part bifurcated) are observed.

Comment top

The crystal structure (Fig. 1) of the title compound, [Cu2(HF2)(H2O)8][AlF6].2H2O), is isotypic with [Cu2(HF2)(H2O)8][FeF6].2H2O (Le Bail & Mercier, 2009). Except the Al—F distances (¯d = 1.810 Å versus 1.930 Å for the average Fe—F distance), all other interatomic distances, angles and the hydrogen bond geometry are very similar for the two structures. A detailed description of this structure has been given Le Bail & Mercier (2009).

There is one additional compound described in the Cu/Al/F/O/H system, viz the mineral khaidarkanite with formula Cu4Al3(OH)14F3(H2O)2 (Rastsvetaeva et al., 1997). The latter differs from the title compound as its structure contains distorted [Cu(OH)5(H2O)] octahedra, and [Al(OH)6] and [AlF4(H2O)2] octahedra as building units.

Related literature top

For the structure of the isotypic FeIII analogue, see: Le Bail & Mercier (2009). For a natural compound in the Cu/Al/F/O/H system, Cu4Al3(OH)14F3(H2O)2 (mineral name khaidarkanite), see: Rastsvetaeva et al. (1997).

Experimental top

AlF3 and CuSO4.5H2O (both Merck, p.a.) were reacted hydrothermally in a 2 M HF solution at 393 K for 4 d. Blue crystals of the title compound with mostly platy habit and up to 0.3 mm in length were obtained.

Refinement top

The structure was solved using direct methods. For better comparison with the isotypic FeIII analogue (Le Bail & Mercier, 2009), the atomic coordinates of the latter were used for the final refinement cycles. All H atoms were located from difference Fourier maps. The water H atoms were restrained to have O—H distances of 0.85 Å. Their Uiso values were refined with one common parameter. The position of the H atom of the disordered HF group (set with a site occupation factor of 1/2) was fixed during refinement, but its Uiso value was refined independently.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ATOMS for Windows (Dowty, 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The crystal structure of [Cu2(HF2)(H2O)8][AlF6](H2O)2 in polyhedral representation projected along [010]. Colour key: O atoms white, F atoms green, H atoms are grey, [CuO5F] octahedra are blue, [AlF6] octahedra are red. Displacement ellipsoids are given at the 74% probability level; H atoms are displayed as spheres of arbitrary radius. Hydrogen bonds are indicated with green lines. Note that for clarity only one of the disordered H atoms bonded to the F atom is shown.
octaaqua(hydrogendifluorido)dicopper(II) hexafluoridoaluminate dihydrate top
Crystal data top
[Cu2(HF2)(H2O)8][AlF6]·2H2OZ = 1
Mr = 487.23F(000) = 244
Triclinic, P1Dx = 2.228 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.6119 (3) ÅCell parameters from 3443 reflections
b = 7.3410 (3) Åθ = 2.7–30.0°
c = 8.3174 (3) ŵ = 3.12 mm−1
α = 107.336 (1)°T = 293 K
β = 106.715 (1)°Plate, blue
γ = 94.454 (1)°0.18 × 0.14 × 0.06 mm
V = 363.15 (3) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer		2013 independent reflections
Radiation source: fine-focus sealed tube1952 reflections with I > 2σ(I)
graphiteRint = 0.019
ω scansθmax = 30.0°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		h = −9→9
Tmin = 0.52, Tmax = 0.80k = −10→10
3899 measured reflectionsl = −11→11
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)] = 0.026H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.072 w = 1/[σ2(Fo2) + (0.0482P)2 + 0.1517P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
2013 reflectionsΔρmax = 0.44 e Å−3
130 parametersΔρmin = −0.54 e Å−3
10 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.059 (5)
Crystal data top
[Cu2(HF2)(H2O)8][AlF6]·2H2Oγ = 94.454 (1)°
Mr = 487.23V = 363.15 (3) Å3
Triclinic, P1Z = 1
a = 6.6119 (3) ÅMo Kα radiation
b = 7.3410 (3) ŵ = 3.12 mm−1
c = 8.3174 (3) ÅT = 293 K
α = 107.336 (1)°0.18 × 0.14 × 0.06 mm
β = 106.715 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		2013 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		1952 reflections with I > 2σ(I)
Tmin = 0.52, Tmax = 0.80Rint = 0.019
3899 measured reflectionsθmax = 30.0°
Refinement top
R[F2 > 2σ(F2)] = 0.026H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.072Δρmax = 0.44 e Å−3
S = 1.08Δρmin = −0.54 e Å−3
2013 reflectionsAbsolute structure: ?
130 parametersFlack parameter: ?
10 restraintsRogers parameter: ?
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*/UeqOcc. (<1)
Cu0.60564 (3)0.55637 (3)0.23399 (2)0.01836 (10)
Al0.00000.00000.00000.01611 (15)
F10.21626 (18)−0.02274 (17)−0.09157 (16)0.0272 (2)
F20.19296 (18)0.12317 (17)0.21936 (15)0.0282 (2)
F3−0.02395 (19)0.23071 (16)−0.03724 (18)0.0278 (2)
F40.4323 (2)0.5863 (2)0.38450 (18)0.0354 (3)
O10.5678 (2)0.2833 (2)0.2103 (2)0.0289 (3)
O20.6023 (3)0.8243 (2)0.2410 (2)0.0266 (3)
O30.7505 (2)0.5080 (2)0.0522 (2)0.0248 (3)
O40.9127 (2)0.6621 (2)0.4883 (2)0.0278 (3)
O50.2346 (3)0.8900 (2)0.4430 (2)0.0296 (3)
H110.636 (6)0.198 (5)0.160 (5)0.055 (3)*
H120.456 (5)0.233 (5)0.218 (5)0.055 (3)*
H210.668 (6)0.881 (5)0.196 (5)0.055 (3)*
H220.653 (6)0.910 (5)0.340 (4)0.055 (3)*
H310.833 (6)0.586 (5)0.050 (5)0.055 (3)*
H320.811 (6)0.421 (5)0.027 (5)0.055 (3)*
H410.885 (6)0.716 (5)0.583 (4)0.055 (3)*
H421.009 (5)0.644 (5)0.483 (5)0.055 (3)*
H510.213 (6)0.925 (5)0.365 (4)0.055 (3)*
H520.344 (6)0.796 (5)0.435 (5)0.055 (3)*
H60.47220.52260.46290.026 (12)*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu0.02240 (14)0.01519 (13)0.02078 (14)0.00360 (8)0.01130 (9)0.00657 (9)
Al0.0176 (3)0.0141 (3)0.0194 (3)0.0027 (2)0.0093 (2)0.0063 (2)
F10.0279 (5)0.0262 (5)0.0377 (6)0.0082 (4)0.0226 (5)0.0129 (5)
F20.0273 (5)0.0301 (6)0.0225 (5)−0.0007 (4)0.0070 (4)0.0049 (4)
F30.0304 (5)0.0188 (5)0.0424 (6)0.0066 (4)0.0175 (5)0.0161 (5)
F40.0481 (7)0.0379 (7)0.0378 (7)0.0205 (6)0.0281 (6)0.0211 (5)
O10.0280 (7)0.0161 (6)0.0471 (8)0.0040 (5)0.0213 (6)0.0084 (6)
O20.0394 (7)0.0176 (6)0.0273 (6)0.0042 (5)0.0164 (6)0.0091 (5)
O30.0284 (6)0.0189 (6)0.0333 (7)0.0049 (5)0.0200 (6)0.0079 (5)
O40.0262 (6)0.0276 (7)0.0280 (6)0.0050 (5)0.0086 (5)0.0073 (5)
O50.0379 (7)0.0279 (7)0.0266 (6)0.0090 (6)0.0134 (6)0.0108 (5)
Geometric parameters (Å, °) top
Cu—F41.9049 (12)Al—F11.8001 (10)
Cu—O11.9441 (14)Al—F1ii1.8001 (10)
Cu—O21.9522 (14)Al—F2ii1.8091 (11)
Cu—O31.9739 (13)Al—F21.8091 (11)
Cu—O42.3463 (15)Al—F3ii1.8209 (11)
Cu—O3i2.7139 (16)Al—F31.8209 (11)
Cu—Cui3.5440 (4)F4—F4iii2.596 (3)
F4—Cu—O186.72 (6)F4iii—F4—O175.78 (7)
F4—Cu—O290.07 (6)Cu—F4—O5120.66 (7)
O1—Cu—O2172.31 (6)F4iii—F4—O5123.74 (8)
F4—Cu—O3172.54 (6)O1—F4—O5159.76 (8)
O1—Cu—O391.01 (6)Cu—F4—O245.67 (4)
O2—Cu—O391.29 (6)F4iii—F4—O2138.16 (10)
F4—Cu—O489.18 (6)O1—F4—O292.70 (6)
O1—Cu—O497.22 (6)O5—F4—O275.99 (6)
O2—Cu—O489.72 (6)H11—O1—H12113 (4)
O3—Cu—O498.16 (6)Cu—O2—Cui65.57 (4)
F4—Cu—O3i89.91 (5)F4—O2—Cui93.18 (5)
O1—Cu—O3i91.35 (6)Cu—O2—H21126 (3)
O2—Cu—O3i81.64 (6)F4—O2—H21169 (3)
O3—Cu—O3i83.04 (5)Cui—O2—H2183 (3)
O4—Cu—O3i171.31 (5)Cu—O2—H22117 (3)
F1—Al—F1ii180.00 (8)F4—O2—H2291 (3)
F1—Al—F2ii90.44 (5)Cui—O2—H22176 (3)
F1ii—Al—F2ii89.56 (5)H21—O2—H2292 (4)
F1—Al—F289.56 (5)Cu—O3—Cui96.96 (5)
F1ii—Al—F290.44 (5)Cu—O3—H31123 (3)
F2ii—Al—F2180.0Cui—O3—H31107 (3)
F1—Al—F3ii89.97 (5)Cu—O3—H32125 (3)
F1ii—Al—F3ii90.03 (5)Cui—O3—H32106 (3)
F2ii—Al—F3ii90.57 (6)H31—O3—H3297 (4)
F2—Al—F3ii89.43 (6)Cu—O4—H41113 (2)
F1—Al—F390.03 (5)F4—O4—H4175 (3)
F1ii—Al—F389.97 (5)Cu—O4—H42121 (3)
F2ii—Al—F389.43 (6)F4—O4—H42156 (3)
F2—Al—F390.57 (6)H41—O4—H42126 (4)
F3ii—Al—F3180.00 (8)F4—O5—H51110 (3)
Cu—F4—F4iii109.26 (8)H51—O5—H52109 (3)
Cu—F4—O147.26 (4)
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x, −y, −z; (iii) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H11···F1iv0.87 (3)1.74 (3)2.6042 (17)171 (4)
O1—H12···F20.83 (3)1.86 (3)2.6899 (18)176 (4)
O2—H21···F1i0.81 (3)1.79 (3)2.6020 (18)172 (4)
O2—H22···O5v0.83 (3)1.86 (3)2.684 (2)178 (4)
O3—H31···F3i0.77 (3)1.82 (3)2.5877 (18)178 (4)
O3—H32···F3vi0.79 (3)1.89 (3)2.6700 (17)174 (4)
O4—H41···F2iii0.85 (3)1.95 (3)2.7840 (19)169 (4)
O4—H42···O4vii0.67 (3)2.41 (4)2.758 (3)115 (4)
O4—H42···O5vi0.67 (3)2.41 (4)2.784 (2)117 (4)
O5—H51···F2viii0.75 (3)2.14 (3)2.8538 (19)159 (4)
O5—H51···F3ix0.75 (3)2.50 (3)3.072 (2)135 (4)
O5—H52···F41.04 (3)1.67 (3)2.6620 (19)158 (3)
F4—H6···F4iii0.9031 (13)1.6945 (13)2.596 (3)175.27 (5)
Symmetry codes: (iv) −x+1, −y, −z; (i) −x+1, −y+1, −z; (v) −x+1, −y+2, −z+1; (vi) x+1, y, z; (iii) −x+1, −y+1, −z+1; (vii) −x+2, −y+1, −z+1; (viii) x, y+1, z; (ix) −x, −y+1, −z.
Table 1
Selected geometric parameters (Å) top
Cu—F41.9049 (12)Cu—O3i2.7139 (16)
Cu—O11.9441 (14)Al—F11.8001 (10)
Cu—O21.9522 (14)Al—F21.8091 (11)
Cu—O31.9739 (13)Al—F31.8209 (11)
Cu—O42.3463 (15)
Symmetry codes: (i) −x+1, −y+1, −z.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H11···F1ii0.87 (3)1.74 (3)2.6042 (17)171 (4)
O1—H12···F20.83 (3)1.86 (3)2.6899 (18)176 (4)
O2—H21···F1i0.81 (3)1.79 (3)2.6020 (18)172 (4)
O2—H22···O5iii0.83 (3)1.86 (3)2.684 (2)178 (4)
O3—H31···F3i0.77 (3)1.82 (3)2.5877 (18)178 (4)
O3—H32···F3iv0.79 (3)1.89 (3)2.6700 (17)174 (4)
O4—H41···F2v0.85 (3)1.95 (3)2.7840 (19)169 (4)
O4—H42···O4vi0.67 (3)2.41 (4)2.758 (3)115 (4)
O4—H42···O5iv0.67 (3)2.41 (4)2.784 (2)117 (4)
O5—H51···F2vii0.75 (3)2.14 (3)2.8538 (19)159 (4)
O5—H51···F3viii0.75 (3)2.50 (3)3.072 (2)135 (4)
O5—H52···F41.04 (3)1.67 (3)2.6620 (19)158 (3)
F4—H6···F4v0.9031 (13)1.6945 (13)2.596 (3)175.27 (5)
Symmetry codes: (ii) −x+1, −y, −z; (i) −x+1, −y+1, −z; (iii) −x+1, −y+2, −z+1; (iv) x+1, y, z; (v) −x+1, −y+1, −z+1; (vi) −x+2, −y+1, −z+1; (vii) x, y+1, z; (viii) −x, −y+1, −z.
references
References top

Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Dowty, E. (2006). ATOMS for Windows. Shape Software, Kingsport, Tennessee, USA.

Le Bail, A. & Mercier, A.-M. (2009). Acta Cryst. E65, i23–i24.

Rastsvetaeva, R. K., Chukanov, N. V. & Karpenko, V. Yu. (1997). Dokl. Akad. Nauk, 353, 354-357.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.