Hexaaqua­dibromidoeuropium(III) bromide, [EuBr2(H2O)6]Br

Hoch, C.; Simon, A.

doi:10.1107/S1600536808014359

inorganic compounds

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Volume 64| Part 6| June 2008| Page i35

doi:10.1107/S1600536808014359

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Hexaaquadibromidoeuropium(III) bromide, [EuBr₂(H₂O)₆]Br

Constantin Hoch ^a ^* and Arndt Simon ^a

^aMax-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
^*Correspondence e-mail: c.hoch@fkf.mpg.de

(Received 5 May 2008; accepted 13 May 2008; online 17 May 2008)

The title compound crystallizes with the GdCl₃·6H₂O structure type, exhibiting discrete [EuBr₂(H₂O)₆]⁺ cations as the main building blocks, linked with isolated bromide anions via H⋯Br hydrogen bonds to form a complex framework. The Eu atom and one Br atom each lie on a twofold rotation axis.

Related literature

For related literature, see: Bärnighausen et al. (1965 ); Bell & Smith (1990 ); Burns & Peterson (1971 ); Demyanets et al. (1974 ); Duhlev et al. (1988 ); Graeber et al. (1966 ); Habenschuss & Spedding (1980 ); Junk et al. (1999 ); Kolitsch (2006 ); Marezio et al. (1961 ); Reuter et al. (1994 ); Tegenfeldt et al. (1979 ); Wickleder & Meyer (1995 ).

Experimental

Crystal data

[EuBr₂(H₂O)₆]Br
M_r = 499.79
Monoclinic, P 2/c
a = 8.1672 (7) Å
b = 6.7538 (4) Å
c = 12.5451 (10) Å
β = 127.077 (5)°
V = 552.08 (8) Å³
Z = 2
Mo Kα radiation
μ = 16.52 mm⁻¹
T = 293 (2) K
0.25 × 0.24 × 0.18 mm

Data collection

Stoe IPDSII diffractometer
Absorption correction: numerical [X-RED (Stoe & Cie, 2001 ) and X-SHAPE (Stoe & Cie, 1999 )] T_min = 0.065, T_max = 0.155
10921 measured reflections
1613 independent reflections
1397 reflections with I > 2s(I)
R_int = 0.067

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.049
S = 1.11
1613 reflections
72 parameters
All H-atom parameters refined
Δρ_max = 1.14 e Å⁻³
Δρ_min = −1.10 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Eu1—Br1	2.9449 (5)
Eu1—O1	2.424 (3)
Eu1—O2	2.422 (3)
Eu1—O3	2.388 (3)

Br1—Eu1—O1	146.89 (8)
Br1—Eu1—O1ⁱ	76.21 (9)
Br1—Eu1—O2	77.33 (8)
Br1—Eu1—O2ⁱ	78.22 (8)
Br1—Eu1—O3	107.21 (9)
Br1—Eu1—O3ⁱ	143.18 (8)
Br1—Eu1—Br1ⁱ	84.41 (2)
O1—Eu1—O1ⁱ	132.3 (2)
O2—Eu1—O2ⁱ	146.8 (2)
O3—Eu1—O3ⁱ	84.5 (2)
O1—Eu1—O2	72.6 (1)
O1—Eu1—O2ⁱ	122.0 (1)
O1—Eu1—O3	75.8 (1)
O1—Eu1—O3ⁱ	69.3 (1)
O2—Eu1—O3	70.9 (1)
O2—Eu1—O3ⁱ	138.6 (1)
Symmetry code: (i) $[-x+1, y, -z+{\script{1\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H11⋯Br2ⁱⁱ	0.83 (2)	2.53 (8)	3.343 (4)	168 (6)
O1—H12⋯Br1ⁱⁱⁱ	0.83 (2)	2.52 (13)	3.333 (4)	165 (6)
O2—H21⋯Br1^iv	0.82 (2)	2.49 (10)	3.307 (4)	172 (6)
O2—H22⋯Br2^v	0.83 (2)	2.63 (11)	3.417 (4)	161 (6)
O3—H31⋯Br1^vi	0.83 (2)	2.46 (8)	3.288 (4)	173 (6)
O3—H32⋯Br2	0.83 (2)	2.52 (11)	3.328 (5)	163 (6)
Symmetry codes: (ii) -x, -y+1, -z; (iii) $[x-1, -y, z-{\script{1\over 2}}]$ ; (iv) -x+1, -y, -z+1; (v) x, y-1, z; (vi) x, y+1, z.

Data collection: X-AREA (Stoe & Cie, 2006 ); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DRAWXTL (Finger et al., 2007 ); software used to prepare material for publication: PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808014359/mg2051sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808014359/mg2051Isup2.hkl

checkCIF report

Comment top

[EuBr₂(H₂O)₆]Br crystallizes in the monoclinic space group P2/c (No. 13) and is isotypic with the GdCl₃^.6H₂O structure type (Marezio et al., 1961), like many chloride hexahydrates MCl₃^.6H₂O with M = Y (Bell & Smith, 1990), Ce (Reuter et al., 1994), Nd (Habenschuss & Spedding, 1980), Sm - Tm (Graeber et al., 1966), Am, Bk (Burns & Peterson, 1971), and two bromide hexahydrates MBr₃^.6H₂O (M = Pr, Dy, Junk et al., 1999).

The Eu atoms in [EuBr₂(H₂O)₆]Br are coordinated by six water molecules and two bromine atoms forming a distorted square antiprism (Fig. 1). Hydrogen bonds H—Br connect the [EuBr₂(H₂O)₆]⁺ cations with the Br^- counter-anions to a network. The bromine atom Br1 belonging to the cationic complex is surrounded by four, the isolated bromine atom Br2 by six hydrogen bonds (Fig. 2). A view of the unit cell of [EuBr₂(H₂O)₆]Br is given in Fig. 3.

The H—Br distances (2.46–2.63 Å) are in good agreement with those in other bromide hydrates (e.g. 2.38–2.54 Å in [Sc(H₂O)₅(OH)]Br₂, Kolitsch, 2006; 2.32–2.80 Å in [Ca(H₂O)₆]₂[CdBr₆], Duhlev et al., 1988; 2.40–2.83 A in NaBr^.2H₂O, Tegenfeldt et al., 1979). The Eu^III—O distances in [EuBr₂(H₂O)₆]Br range from 2.39 to 2.42 Å and thus are very similar to those in EuCl₃^.3H₂O (2.39–2.40 Å, Reuter et al., 1994), EuCl₃^.6H₂O (2.39–2.43 Å, Graeber et al., 1966), or EuCl(OH)₂ (2.35–2.44 Å, Demyanets et al., 1974). The same holds for the Eu^III—Br distances in [EuBr₂(H₂O)₆]Br (2.94 Å) which lie between those in Na₃EuBr₆ (2.83 Å, Wickleder & Meyer, 1995) and those in EuOBr (3.19 Å, Bärnighausen et al., 1965).

Related literature top

For related literature, see: Bärnighausen et al. (1965); Bell & Smith (1990); Burns & Peterson (1971); Demyanets et al. (1974); Duhlev et al. (1988); Graeber et al. (1966); Habenschuss & Spedding (1980); Junk et al. (1999); Kolitsch (2006); Marezio et al. (1961); Reuter et al. (1994); Tegenfeldt et al. (1979); Wickleder & Meyer (1995).

Experimental top

Colourless single crystals of [EuBr₂(H₂O)₆]Br were obtained by recrystallizing the commercially available product ("EuBr₃^.X H₂O", Alfa Aesar, 99.99%) under argon from degassed aqueous HBr solution by slow cooling of a solution saturated at ca 60 °C to room temperature.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2006); cell refinement: X-AREA (Stoe & Cie, 2006); data reduction: X-AREA (Stoe & Cie, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DRAWXTL (Finger et al., 2007); software used to prepare material for publication: PLATON (Spek, 2003).

Figures top

	Fig. 1. View of the cationic [Eu(H₂O)₆Br₂]⁺ unit in [Eu(H₂O)₆Br₂]Br, with displacement ellipsoids drawn at the 90% propability level. H atoms are shown as black spheres of arbitrary radii. [Symmetry code: (i) -x, y, 1/2 - z.]
	Fig. 2. View of the H—Br contacts in [Eu(H₂O)₆Br(2)₂]Br(1), left: four hydrogen bonds link Br1 to water molecules, right: six hydrogen bonds link Br2 to water molecules. All displacement ellipsoids are drawn at the 90% propability level. [Symmetry codes: (i) -x, y, 1/2 - z; (ii) -x, -y, -z; (iii) x, -y, 1/2 + z.]
	Fig. 3. View along (010) on the crystal structure of [Eu(H₂O)₆Br₂]Br. Small black spheres represent H atoms, large black spheres represent Eu atoms, grey spheres represent Br atoms, light grey spheres represent O atoms. Grey polyhedra represent the coordination of H atoms around Br atoms.

Hexaaquadibromidoeuropium(III) bromide top

Crystal data top

[EuBr₂(H₂O)₆]Br	F(000) = 456
M_r = 499.79	D_x = 3.006 Mg m⁻³
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 10367 reflections
a = 8.1672 (7) Å	θ = 3.0–32.1°
b = 6.7538 (4) Å	µ = 16.52 mm⁻¹
c = 12.5451 (10) Å	T = 293 K
β = 127.077 (5)°	Irregular polyhedron, clear colourless
V = 552.08 (8) Å³	0.25 × 0.24 × 0.18 mm
Z = 2

Data collection top

Stoe IPDSII diffractometer	1613 independent reflections
Radiation source: fine-focus sealed tube	1397 reflections with I > 2s(I)
Graphite monochromator	R_int = 0.067
ω scans (in two runs with ϕ₁ = 0° and ϕ₂ = 90°)	θ_max = 30.0°, θ_min = 3.0°
Absorption correction: numerical [X-RED (Stoe & Cie, 2001) and X-SHAPE (Stoe & Cie, 1999)]	h = −11→11
T_min = 0.065, T_max = 0.155	k = −9→9
10921 measured reflections	l = −17→17

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.028	All H-atom parameters refined
wR(F²) = 0.049	w = 1/[σ²(F_o²) + (0.0169P)²] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max < 0.001
1613 reflections	Δρ_max = 1.14 e Å⁻³
72 parameters	Δρ_min = −1.10 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: 0.0409 (10)

Crystal data top

[EuBr₂(H₂O)₆]Br	V = 552.08 (8) Å³
M_r = 499.79	Z = 2
Monoclinic, P2/c	Mo Kα radiation
a = 8.1672 (7) Å	µ = 16.52 mm⁻¹
b = 6.7538 (4) Å	T = 293 K
c = 12.5451 (10) Å	0.25 × 0.24 × 0.18 mm
β = 127.077 (5)°

Data collection top

Stoe IPDSII diffractometer	1613 independent reflections
Absorption correction: numerical [X-RED (Stoe & Cie, 2001) and X-SHAPE (Stoe & Cie, 1999)]	1397 reflections with I > 2s(I)
T_min = 0.065, T_max = 0.155	R_int = 0.067
10921 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	0 restraints
wR(F²) = 0.049	All H-atom parameters refined
S = 1.11	Δρ_max = 1.14 e Å⁻³
1613 reflections	Δρ_min = −1.10 e Å⁻³
72 parameters

Special details top

Experimental. The title compoud is a commercially available chemical (Alfa Aesar) and was recrystallized under argon from degassed aqueous HBr solution. A suitable single-crystal was sealed with mother liquor in a thin-walled glass capillary.

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

	x	y	z	U_iso*/U_eq
Eu1	0.50000	0.16454 (4)	0.25000	0.0170 (1)
Br1	0.70613 (6)	−0.15845 (7)	0.44669 (4)	0.0295 (1)
Br2	0.00000	0.63151 (9)	0.25000	0.0318 (2)
O1	0.1772 (5)	0.3097 (5)	0.0676 (3)	0.0320 (7)
O2	0.2413 (5)	0.0620 (5)	0.2757 (4)	0.0313 (7)
O3	0.4434 (5)	0.4262 (5)	0.3524 (4)	0.0335 (7)
H11	0.148 (11)	0.336 (10)	−0.006 (4)	0.06 (2)*
H12	0.072 (9)	0.258 (14)	0.050 (10)	0.10 (3)*
H21	0.253 (12)	0.098 (11)	0.342 (5)	0.07 (2)*
H22	0.183 (11)	−0.046 (6)	0.253 (9)	0.09 (3)*
H31	0.518 (10)	0.526 (7)	0.376 (8)	0.08 (2)*
H32	0.321 (5)	0.456 (12)	0.315 (8)	0.09 (3)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Eu1	0.0168 (1)	0.0180 (1)	0.0172 (1)	0.000	0.0109 (1)	0.000
Br1	0.0295 (2)	0.0293 (2)	0.0266 (3)	0.0027 (2)	0.0152 (2)	0.0066 (2)
Br2	0.0294 (3)	0.0360 (3)	0.0327 (4)	0.000	0.0202 (3)	0.000
O1	0.0233 (13)	0.0385 (17)	0.0256 (18)	0.0036 (12)	0.0102 (13)	0.0084 (14)
O2	0.0316 (15)	0.0367 (17)	0.0355 (19)	−0.0076 (13)	0.0254 (15)	−0.0055 (14)
O3	0.0308 (15)	0.0302 (15)	0.042 (2)	−0.0035 (13)	0.0229 (16)	−0.0106 (14)

Geometric parameters (Å, º) top

Eu1—Br1	2.9449 (5)	Eu1—O3ⁱ	2.388 (3)
Eu1—Br1ⁱ	2.9449 (5)	O1—H11	0.82 (2)
Eu1—O1	2.424 (3)	O1—H12	0.83 (2)
Eu1—O1ⁱ	2.424 (3)	O2—H21	0.82 (2)
Eu1—O2	2.422 (3)	O2—H22	0.82 (2)
Eu1—O2ⁱ	2.422 (3)	O3—H31	0.83 (2)
Eu1—O3	2.388 (3)	O3—H32	0.83 (2)

Br1—Eu1—O1	146.89 (8)	O1—Eu1—O2	72.6 (1)
Br1ⁱ—Eu1—O1ⁱ	146.89 (8)	O1ⁱ—Eu1—O2ⁱ	72.6 (1)
Br1—Eu1—O1ⁱ	76.21 (9)	O1—Eu1—O2ⁱ	122.0 (1)
Br1ⁱ—Eu1—O1	76.21 (9)	O1ⁱ—Eu1—O2	122.0 (1)
Br1—Eu1—O2	77.33 (8)	O1—Eu1—O3	75.8 (1)
Br1ⁱ—Eu1—O2ⁱ	77.33 (8)	O1ⁱ—Eu1—O3ⁱ	75.8 (1)
Br1—Eu1—O2ⁱ	78.22 (8)	O1—Eu1—O3ⁱ	69.3 (1)
Br1ⁱ—Eu1—O2	78.22 (8)	O1ⁱ—Eu1—O3	69.3 (1)
Br1—Eu1—O3	107.21 (9)	O2—Eu1—O3	70.9 (1)
Br1ⁱ—Eu1—O3ⁱ	107.21 (9)	O2ⁱ—Eu1—O3ⁱ	70.9 (1)
Br1—Eu1—O3ⁱ	143.18 (8)	O2—Eu1—O3ⁱ	138.6 (1)
Br1ⁱ—Eu1—O3	143.18 (8)	O2ⁱ—Eu1—O3	138.6 (1)
Br1—Eu1—Br1ⁱ	84.41 (2)	H11—O1—H12	104 (8)
O1—Eu1—O1ⁱ	132.3 (2)	H21—O2—H22	107 (8)
O2—Eu1—O2ⁱ	146.8 (2)	H31—O3—H32	112 (8)
O3—Eu1—O3ⁱ	84.5 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H11···Br2ⁱⁱ	0.83 (2)	2.53 (8)	3.343 (4)	168 (6)
O1—H12···Br1ⁱⁱⁱ	0.83 (2)	2.52 (13)	3.333 (4)	165 (6)
O2—H21···Br1^iv	0.82 (2)	2.49 (10)	3.307 (4)	172 (6)
O2—H22···Br2^v	0.83 (2)	2.63 (11)	3.417 (4)	161 (6)
O3—H31···Br1^vi	0.83 (2)	2.46 (8)	3.288 (4)	173 (6)
O3—H32···Br2	0.83 (2)	2.52 (11)	3.328 (5)	163 (6)

Symmetry codes: (ii) −x, −y+1, −z; (iii) x−1, −y, z−1/2; (iv) −x+1, −y, −z+1; (v) x, y−1, z; (vi) x, y+1, z.

Experimental details

Crystal data
Chemical formula	[EuBr₂(H₂O)₆]Br
M_r	499.79
Crystal system, space group	Monoclinic, P2/c
Temperature (K)	293
a, b, c (Å)	8.1672 (7), 6.7538 (4), 12.5451 (10)
β (°)	127.077 (5)
V (Å³)	552.08 (8)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	16.52
Crystal size (mm)	0.25 × 0.24 × 0.18

Data collection
Diffractometer	Stoe IPDSII diffractometer
Absorption correction	Numerical [X-RED (Stoe & Cie, 2001) and X-SHAPE (Stoe & Cie, 1999)]
T_min, T_max	0.065, 0.155
No. of measured, independent and observed [I > 2s(I)] reflections	10921, 1613, 1397
R_int	0.067
(sin θ/λ)_max (Å⁻¹)	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.049, 1.11
No. of reflections	1613
No. of parameters	72
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	1.14, −1.10

Computer programs: X-AREA (Stoe & Cie, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DRAWXTL (Finger et al., 2007), PLATON (Spek, 2003).

Selected geometric parameters (Å, º) top

Eu1—Br1	2.9449 (5)	Eu1—O3ⁱ	2.388 (3)
Eu1—Br1ⁱ	2.9449 (5)	O1—H11	0.82 (2)
Eu1—O1	2.424 (3)	O1—H12	0.83 (2)
Eu1—O1ⁱ	2.424 (3)	O2—H21	0.82 (2)
Eu1—O2	2.422 (3)	O2—H22	0.82 (2)
Eu1—O2ⁱ	2.422 (3)	O3—H31	0.83 (2)
Eu1—O3	2.388 (3)	O3—H32	0.83 (2)

Br1—Eu1—O1	146.89 (8)	O1—Eu1—O2	72.6 (1)
Br1ⁱ—Eu1—O1ⁱ	146.89 (8)	O1ⁱ—Eu1—O2ⁱ	72.6 (1)
Br1—Eu1—O1ⁱ	76.21 (9)	O1—Eu1—O2ⁱ	122.0 (1)
Br1ⁱ—Eu1—O1	76.21 (9)	O1ⁱ—Eu1—O2	122.0 (1)
Br1—Eu1—O2	77.33 (8)	O1—Eu1—O3	75.8 (1)
Br1ⁱ—Eu1—O2ⁱ	77.33 (8)	O1ⁱ—Eu1—O3ⁱ	75.8 (1)
Br1—Eu1—O2ⁱ	78.22 (8)	O1—Eu1—O3ⁱ	69.3 (1)
Br1ⁱ—Eu1—O2	78.22 (8)	O1ⁱ—Eu1—O3	69.3 (1)
Br1—Eu1—O3	107.21 (9)	O2—Eu1—O3	70.9 (1)
Br1ⁱ—Eu1—O3ⁱ	107.21 (9)	O2ⁱ—Eu1—O3ⁱ	70.9 (1)
Br1—Eu1—O3ⁱ	143.18 (8)	O2—Eu1—O3ⁱ	138.6 (1)
Br1ⁱ—Eu1—O3	143.18 (8)	O2ⁱ—Eu1—O3	138.6 (1)
Br1—Eu1—Br1ⁱ	84.41 (2)	H11—O1—H12	104 (8)
O1—Eu1—O1ⁱ	132.3 (2)	H21—O2—H22	107 (8)
O2—Eu1—O2ⁱ	146.8 (2)	H31—O3—H32	112 (8)
O3—Eu1—O3ⁱ	84.5 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H11···Br2ⁱⁱ	0.83 (2)	2.53 (8)	3.343 (4)	168 (6)
O1—H12···Br1ⁱⁱⁱ	0.83 (2)	2.52 (13)	3.333 (4)	165 (6)
O2—H21···Br1^iv	0.82 (2)	2.49 (10)	3.307 (4)	172 (6)
O2—H22···Br2^v	0.83 (2)	2.63 (11)	3.417 (4)	161 (6)
O3—H31···Br1^vi	0.83 (2)	2.46 (8)	3.288 (4)	173 (6)
O3—H32···Br2	0.83 (2)	2.52 (11)	3.328 (5)	163 (6)

Symmetry codes: (ii) −x, −y+1, −z; (iii) x−1, −y, z−1/2; (iv) −x+1, −y, −z+1; (v) x, y−1, z; (vi) x, y+1, z.

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Volume 64| Part 6| June 2008| Page i35

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