Redetermination of [EuCl2(H2O)6]Cl.

The crystal structure of the title compound, hexa-aqua-dichlorido-europium(III) chloride, was redetermined with modern crystallographic methods. In comparison with the previous study [Lepert et al. (1983 ▶). Aust. J. Chem. 36, 477-482], it could be shown that the atomic coordinates of some O atoms had been confused and now were corrected. Moreover, it was possible to freely refine the positions of the H atoms and thus to improve the accurracy of the crystal structure. [EuCl2(H2O)6]Cl crystallizes with the GdCl3·6H2O structure-type, exhibiting discrete [EuCl2(H2O)6](+) cations as the main building blocks. The main blocks are linked with isolated chloride anions via O-H⋯Cl hydrogen bonds into a three-dimensional framework. The Eu(3+) cation is located on a twofold rotation axis and is coordinated in the form of a Cl2O6 square anti-prism. One chloride anion coordinates directly to Eu(3+), whereas the other chloride anion, situated on a twofold rotation axis, is hydrogen bonded to six octa-hedrally arranged water mol-ecules.

Related literature

For previous structure determinations of the title compound, see: Lepert et al. (1983 ▶); Bel’skii & Struchkov (1965 ▶). For the GdCl3·6H2O structure type and isotypic compounds, see: Marezio et al. (1961 ▶); Bell & Smith (1990 ▶); Burns & Peterson (1971 ▶); Graeber et al. (1966 ▶); Habenschuss & Spedding (1980 ▶); Hoch & Simon (2008 ▶); Junk et al. (1999 ▶); Reuter et al. (1994 ▶). For related structures, see: Demyanets et al. (1974 ▶); Reuter et al. (1994 ▶). For standardization of crystal data, see: Gelato & Parthé (1987 ▶).

Experimental

Crystal data

[EuCl2(H2O)6]Cl

M = 366.41

Monoclinic,

a = 9.6438 (12) Å

b = 6.5322 (10) Å

c = 7.929 (3) Å

β = 93.653 (13)°

V = 498.4 (2) Å3

Z = 2

Ag Kα radiation

λ = 0.56083 Å

μ = 3.74 mm−1

T = 293 K

0.23 × 0.20 × 0.18 mm

Data collection

Stoe IPDS I diffractometer

Absorption correction: multi-scan (MulScanAbs in PLATON; Spek, 2009 ▶) T min = 0.425, T max = 0.510

13401 measured reflections

1762 independent reflections

1653 reflections with I > 2σ(I)

R int = 0.043

Refinement

R[F 2 > 2σ(F 2)] = 0.015

wR(F 2) = 0.032

S = 1.03

1762 reflections

66 parameters

All H-atom parameters refined

Δρmax = 0.63 e Å−3

Δρmin = −0.77 e Å−3

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: DIAMOND (Crystal Impact, 2007 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536814010307/wm5012sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814010307/wm5012Isup2.hkl

CCDC reference: 1001456

Additional supporting information: crystallographic information; 3D view; checkCIF report

[EuCl2(H2O)6]Cl	Z = 2
Mr = 366.41	F(000) = 348
Monoclinic, P2/n	Dx = 2.441 Mg m−3
Hall symbol: -P 2yac	Ag Kα radiation, λ = 0.56083 Å
a = 9.6438 (12) Å	Cell parameters from 13548 reflections
b = 6.5322 (10) Å	µ = 3.74 mm−1
c = 7.929 (3) Å	T = 293 K
β = 93.653 (13)°	Stretched cuboid, clear colourless
V = 498.4 (2) Å3	0.23 × 0.20 × 0.18 mm

Stoe IPDS I diffractometer	1762 independent reflections
Radiation source: fine-focus sealed tube	1653 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.043
φ scan	θmax = 25.5°, θmin = 3.0°
Absorption correction: multi-scan (MulScanAbs in PLATON; Spek, 2009)	h = −14→14
Tmin = 0.425, Tmax = 0.510	k = −10→10
13401 measured reflections	l = −11→11

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)] = 0.015	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.032	All H-atom parameters refined
S = 1.03	w = 1/[σ2(Fo2) + (0.015P)2] where P = (Fo2 + 2Fc2)/3
1762 reflections	(Δ/σ)max < 0.001
66 parameters	Δρmax = 0.63 e Å−3
0 restraints	Δρmin = −0.77 e Å−3

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
Eu1	0.7500	0.150918 (18)	0.2500	0.01345 (3)
Cl1	0.44156 (5)	0.16532 (7)	0.76010 (6)	0.02588 (9)
Cl2	0.7500	0.62387 (11)	0.7500	0.02813 (13)
O1	0.85427 (18)	0.4256 (2)	0.0872 (2)	0.0275 (3)
O2	0.78164 (18)	0.0484 (2)	0.9561 (2)	0.0263 (3)
O3	0.56055 (17)	0.3002 (2)	0.1060 (2)	0.0278 (3)
H1	0.827 (4)	0.454 (6)	0.001 (5)	0.051 (4)*
H2	0.846 (3)	0.084 (5)	0.902 (4)	0.035 (3)*
H3	0.766 (4)	−0.063 (7)	0.933 (5)	0.058 (5)*
H4	0.551 (4)	0.265 (6)	0.020 (5)	0.052 (5)*
H5	0.881 (4)	0.520 (5)	0.129 (5)	0.040 (3)*
H6	0.491 (4)	0.319 (6)	0.152 (5)	0.044 (4)*

	U11	U22	U33	U12	U13	U23
Eu1	0.01398 (5)	0.01346 (5)	0.01244 (6)	0.000	−0.00293 (3)	0.000
Cl1	0.02417 (18)	0.02396 (18)	0.0286 (2)	−0.00652 (16)	−0.00541 (16)	0.00198 (17)
Cl2	0.0297 (3)	0.0305 (3)	0.0235 (3)	0.000	−0.0033 (2)	0.000
O1	0.0368 (8)	0.0229 (6)	0.0214 (8)	−0.0100 (6)	−0.0085 (6)	0.0038 (5)
O2	0.0336 (7)	0.0277 (7)	0.0175 (7)	−0.0047 (6)	−0.0001 (6)	−0.0039 (5)
O3	0.0250 (6)	0.0317 (7)	0.0250 (8)	0.0067 (5)	−0.0113 (6)	−0.0028 (5)

Eu1—O1	2.4618 (15)	O2—H3	0.76 (4)
Eu1—O1i	2.4618 (16)	O2—H2	0.81 (3)
Eu1—O2ii	2.4620 (18)	O3—H4	0.72 (4)
Eu1—O2iii	2.4620 (18)	O3—H6	0.79 (4)
Eu1—O3	2.3078 (16)	Cl1—H2	2.535 (4)
Eu1—O3i	2.3078 (15)	Cl1—H4	2.3535 (4)
Eu1—Cl1iv	2.7690 (12)	Cl1—H5vi	2.36 (3)
Eu1—Cl1v	2.7690 (12)	Cl2—H1i	2.36 (4)
O1—H1	0.74 (4)	Cl2—H3vii	2.5071 (4)
O1—H5	0.74 (4)	Cl2—H6viii	2.53 (4)
Eu1—O1—H1	122 (3)	O1—Eu1—O2ii	67.83 (6)
Eu1—O1—H1	122 (3)	O1i—Eu1—Cl1iv	105.35 (5)
Eu1—O1—H5	121 (3)	O1—Eu1—Cl1iv	145.35 (4)
Eu1—O1—H5	121 (3)	O2ii—Eu1—O2iii	148.45 (8)
Eu1ix—O2—H2	124 (3)	O2ii—Eu1—Cl1iv	83.83 (4)
Eu1ix—O2—H2	124 (3)	O2iii—Eu1—Cl1iv	72.65 (4)
Eu1ix—O2—H3	117 (3)	O3i—Eu1—O1i	76.70 (6)
Eu1ix—O2—H3	117 (3)	O3—Eu1—O1i	67.31 (6)
Eu1—O3—H4	112 (3)	O3i—Eu1—O2ii	116.15 (7)
Eu1—O3—H4	112 (3)	O3—Eu1—O2ii	77.82 (6)
Eu1—O3—H6	120 (3)	O3i—Eu1—O3	130.01 (8)
Eu1—O3—H6	120 (3)	O3i—Eu1—Cl1iv	146.64 (4)
O1i—Eu1—O1	86.43 (9)	O3—Eu1—Cl1iv	78.18 (5)
O1i—Eu1—O2ii	140.68 (5)	Cl1iv—Eu1—Cl1v	83.51 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Cl2ii	0.74 (4)	2.36 (4)	3.081 (2)	166.08
O2—H2···Cl1iii	0.81 (3)	2.54 (3)	3.351 (2)	174.97
O2—H3···Cl2x	0.76 (4)	2.51 (4)	3.2234 (19)	157.37
O3—H4···Cl1ii	0.72 (4)	2.35 (4)	3.036 (2)	160.44
O1—H5vi···Cl1	0.74 (2)	2.36 (3)	3.095 (2)	173.89
O3—H6···Cl2viii	0.79 (4)	2.53 (4)	3.310 (2)	170.66

Table 1

Selected bond lengths (Å)

Eu1—O1	2.4618 (15)
Eu1—O2i	2.4620 (18)
Eu1—O3	2.3078 (16)
Eu1—Cl1ii	2.7690 (12)

Symmetry codes: (i) ; (ii) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯Cl2i	0.74 (4)	2.36 (4)	3.081 (2)	166.08
O2—H2⋯Cl1iii	0.81 (3)	2.54 (3)	3.351 (2)	174.97
O2—H3⋯Cl2iv	0.76 (4)	2.51 (4)	3.2234 (19)	157.37
O3—H4⋯Cl1i	0.72 (4)	2.35 (4)	3.036 (2)	160.44
O1—H5v⋯Cl1	0.74 (2)	2.36 (3)	3.095 (2)	173.89
O3—H6⋯Cl2vi	0.79 (4)	2.53 (4)	3.310 (2)	170.66

Symmetry codes: (i) ; (iii) ; (iv) ; (v) ; (vi) .