Hydrogen bonding and structure of Ba₂Ru₂Cl₁₀O·10H₂O

Dibarium μ-oxido-bis­[penta­chloridoruthenate(IV)] deca­hydrate, Ba₂Ru₂Cl₁₀O·10H₂O, has been prepared from ruthenium(III) chloride and barium chloride in hydro­chloric acid. It crystallizes in the monoclinic system (space group C2/­c). The structure consists of alternating layers of [Ru₂­Cl₁₀O]⁴⁻ and [Ba(H₂O)₇]²⁺ complex ions along the a direction. The O atom bonded to ruthenium occupies the 4e site, with symmetry, while the other atoms occupy general 8f sites. The overall structure is held together by O—H...O hydrogen bonds and O—H...Cl dipole–dipole inter­actions.

S1. Comment

Previous investigations of MCl₂—RuCl₃ systems (M = K and Cs) have led to the identification of K₄[Ru₂Cl₁₀O] (Deloume et al., 1979) and Cs₄Ru₂Cl₁₀O (Santana Da Silva et al., 1999). We have investigated the hydrated systems MCl₂—RuCl₃—H₂O (M = Mg, Ca and Ba) and, just recently, we have determined the structure of Mg₂Ru₂Cl₁₀O.16H₂O (Boufas et al., 2007). The structural study of the different phases of these systems has been performed in order to compare the cation coordination environments and the number of water molecules, and to study the Ru₂Cl₁₀O anionic group and understand the effect of the Mg/Ba substitution.

The asymmetric unit of the title compound contains one [Ru₂Cl₁₀O]^4- anion, one Ba²⁺ cation and five water molecules (Fig. 1). The overall structure consists of layers stacked along the c direction, with [Ru₂Cl₁₀O]^4- dimeric units bridging adjacent sheets that are held together by [Ba(H₂O)₇]²⁺ cations through the Cl atoms Cl2 and Cl3 along the (101) plane. As reported for Mg₂Ru₂Cl₁₀O.16H₂O (Boufas et al., 2007), the Ru atom resides in a distorted octahedron involving one bridging O atom [Ru1—O1 bond is 1.7657 (4) Å] and five Cl atoms with an Ru—Cl average distance of 2.3637 Å (Table 1). These distances are similar to those of the anhydrous compounds reported in the literature (1.800 and 2.362 Å for K₄[Ru₂Cl₁₀O], and 1.791 and 2.357 Å for Cs₄Ru₂Cl₁₀O] and agree well with those found in Mg₂Ru₂Cl₁₀O.16H₂O (1.7822 and 2.36284 Å). The standard deviations from the values given by the two hydrated compounds differ by about 0.02 and 0.0008 Å. The Ru—O distance in the title compound is the shortest and the Ru—Cl distance is the longest.

The barium cation is surrounded by nine atoms, viz. five O atoms belonging to five water molecules via metal–OH₂ bonds and two Cl atoms (Cl2 and Cl3) from the Ru₂Cl₁₀O octahedron via metal–Cl bonds. The presence of additional interactions (Ba1—O2Wⁱ and Ba1—O4Wⁱ) leads to ninefold coordination for each Ba atom. The [Ba(H₂O)₇]²⁺ cations extend along the b direction in a zigzag fashion, forming layers parallel to the bc plane, and each [Ru₂Cl₁₀O]^4- anion is surrounded by six [Ba(H₂O)₇]²⁺ cations (Fig. 2). The Ba1—Cl2 and Ba1—Cl3 distances (Table 1) are similar to those found in barium dichloride dihydrate (3.0901 and 3.2836 Å; Bochkova et al., 1980) and agree with the sum of the ionic radii of the Ba²⁺ (1.35 Å) and Cl^- ions (1.81 Å) (Shannon, 1976).

The average Ba—Ow distance is 2.8724 Å, similar to that in Ba(OH)I(H₂O)₄ (2.8425 Å), where Ba is coordinated by only four water molecules (Fromm & Goesmann, 2000), and somewhat longer than that in Ba(C₁₀H₄O₈)(H₂O)₅ (2.8094 Å), where Ba is surrounded by five O atoms (Dale et al., 2003). This difference is due to the presence of Ba–carboxylate bonds that reduce the Ba—OH₂ distances.

The cations and anions of the title compound are linked into a three-dimensional network by means of O—H···Cl and O—H···O interactions (Table 2 and Fig. 2). The first type links the Ru₂Cl₁₀O octahedra to water molecules through all the Cl atoms, with distances of between 2.36 (6) and 2.81 (6) Å. Atoms Cl4 and Cl5 are involved in two hydrogen bonds each, Cl2 and Cl3 establish one hydrogen bond each, and Cl1 is engaged in three interactions. The O2W—H12W···Cl1ⁱⁱⁱ interaction is the strongest, with an O—H···Cl distance of 2.36 (6) Å. Only three O—H···O hydrogen bonds are formed via O3W [2.58 (4) Å], O1W [2.25 (9) Å] and O5W [2.20 (7) Å]. The environment of the [Ru₂Cl₁₀O]^4- anion contains nine O—H···Cl dipole–dipole interactions between the anion and the water molecules, i.e. this structure displays a lower degree of cohesion than that reported for Mg₂Ru₂Cl₁₀O.16H₂O characterized by 12 O—H···Cl dipole–dipole interactions and five O—H···O hydrogen bonds.

Overall, the various interactions bridge the ruthenate anions within and between layers and form cavities occupied by the [BaCl₂(H₂O)₇] sheets.

Related literature

For related literature, see: Bochkova et al. (1980); Boufas et al. (2007); Dale (2003); Deloume et al. (1979); Fromm & Goesmann (2000); Santana Da Silva, Zukerman-Schpector, Tfouni & Lever (1999); Shannon (1976); Sheldrick (1997).

S2. Experimental

The title compound was crystallized from a supersaturated hydrochloric acid solution (50%, 5 ml) prepared using doubly distilled water and a mixture of ruthenium(III) chloride trihydrate (2.61 g) and dehydrated barium chloride (2.263 g). Brown plates of Ba₂Ru₂Cl₁₀O.10H₂O were obtained at ambient temperature by slow evaporation of the solution.

S3. Refinement

H atoms were fixed by geometric constraints using the HFIX command (Sheldrick, 1997) and allowed to ride on the attached O atom [this appears to contradict following sentence]. The O—H distances were restrained to 0.85 (s.u. value?) Å to ensure chemically reasonable geometry, with U_iso(H) fixed at 1.5U_eq(O). Please check the values in Table 2; there are minor discrepancies between O—H values here and in _geom_bond_distance.

Computing details

Data collection: COLLECT (Nonius, 2002); cell refinement: DIRAX (Duisenberg, 1992); data reduction: EVAL (Nonius, 2002); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1998) and ATOMS (Dowty, 1995); software used to prepare material for publication: WinGX (Farrugia, 1999) and PARST (Nardelli, 1995).

Figures

	Fig. 1. The structure of the title compound, with the atom-labelling scheme. Displacement ellipsoids for non-H atoms are drawn at the 90% probability level.
	Fig. 2. The packing of the title compound, viewed down the c axis.

dibarium µ-oxo-bis(pentachlororuthenate(IV)) decahydrate

Crystal data

Ba2Ru2Cl10O·10H2O	F(000) = 1912
Mr = 1027.48	Dx = 2.78 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2096 reflections
a = 20.9386 (18) Å	θ = 5.0–26.4°
b = 8.8654 (7) Å	µ = 5.49 mm^−1
c = 16.0560 (15) Å	T = 293 K
β = 124.559 (5)°	Plate, brown
V = 2454.5 (4) Å^3	0.25 × 0.13 × 0.03 mm
Z = 4

Data collection

Nonius KappaCCD diffractometer	2488 independent reflections
Radiation source: fine-focus sealed tube	2103 reflections with I > 2σ(I)
Detector resolution: 9 pixels mm^-1	Rint = 0.05
CCD scans	θmax = 26.4°, θmin = 5°
Absorption correction: part of the refinement model (ΔF) (Sheldrick, 1996 or 1990???)	h = −24→26
Tmin = 0.441, Tmax = 0.862	k = −11→10
10480 measured reflections	l = −20→18

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.070	Only H-atom coordinates refined
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0242P)^2 + 9.3433P] where P = (Fo^2 + 2Fc^2)/3
2488 reflections	(Δ/σ)max = 0.001
144 parameters	Δρmax = 0.53 e Å^−3
15 restraints	Δρmin = −1.28 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ba1	0.190281 (18)	0.46951 (4)	0.66934 (2)	0.03451 (11)
Ru1	0.39877 (2)	0.50729 (4)	0.65883 (2)	0.02010 (11)
Cl1	0.41487 (7)	0.55179 (14)	0.52648 (8)	0.0317 (3)
Cl2	0.37459 (7)	0.45890 (14)	0.78403 (8)	0.0302 (3)
Cl3	0.26475 (6)	0.51664 (14)	0.53772 (8)	0.0320 (3)
Cl4	0.39331 (7)	0.24665 (13)	0.62485 (10)	0.0352 (3)
Cl5	0.39538 (7)	0.76962 (13)	0.68603 (10)	0.0353 (3)
O1	0.5	0.5020 (4)	0.75	0.0204 (9)
O1W	0.0670 (3)	0.2681 (4)	0.5698 (3)	0.0488 (10)
H21W	0.079 (4)	0.183 (5)	0.585 (4)	0.073*
H11W	0.037 (4)	0.271 (7)	0.5060 (10)	0.073*
O2W	0.2671 (2)	0.2783 (4)	0.8455 (3)	0.0374 (8)
H12W	0.304 (3)	0.323 (7)	0.893 (4)	0.056*
H22W	0.234 (3)	0.277 (8)	0.852 (5)	0.056*
O3W	0.0683 (3)	0.5963 (6)	0.6596 (4)	0.0580 (12)
H13W	0.066 (4)	0.634 (9)	0.698 (4)	0.087*
H23W	0.026 (3)	0.576 (10)	0.614 (4)	0.087*
O4W	0.2458 (2)	0.1701 (5)	0.6492 (3)	0.0420 (9)
H24W	0.209 (3)	0.127 (7)	0.596 (4)	0.063*
H14W	0.281 (3)	0.177 (8)	0.645 (5)	0.063*
O5W	0.0767 (2)	0.5701 (5)	0.4729 (3)	0.0459 (9)
H15W	0.043 (4)	0.616 (8)	0.472 (5)	0.069*
H25W	0.081 (4)	0.607 (8)	0.425 (5)	0.069*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ba1	0.02783 (17)	0.03410 (18)	0.03573 (18)	0.00183 (12)	0.01453 (14)	0.00030 (13)
Ru1	0.01603 (18)	0.02381 (19)	0.01740 (18)	−0.00012 (13)	0.00764 (14)	0.00005 (14)
Cl1	0.0326 (6)	0.0405 (7)	0.0246 (5)	0.0010 (5)	0.0178 (5)	0.0030 (5)
Cl2	0.0266 (6)	0.0404 (6)	0.0247 (5)	−0.0029 (5)	0.0153 (5)	0.0011 (5)
Cl3	0.0184 (6)	0.0464 (7)	0.0237 (5)	0.0004 (5)	0.0075 (5)	−0.0041 (5)
Cl4	0.0372 (7)	0.0259 (6)	0.0415 (7)	−0.0035 (5)	0.0218 (6)	−0.0067 (5)
Cl5	0.0336 (6)	0.0288 (6)	0.0417 (7)	0.0015 (5)	0.0202 (6)	0.0004 (5)
O1	0.018 (2)	0.024 (2)	0.018 (2)	0	0.0085 (17)	0
O1W	0.055 (3)	0.033 (2)	0.059 (3)	−0.0048 (19)	0.033 (2)	0.0003 (19)
O2W	0.040 (2)	0.041 (2)	0.0342 (19)	−0.0075 (18)	0.0227 (18)	−0.0021 (16)
O3W	0.048 (3)	0.062 (3)	0.066 (3)	−0.008 (2)	0.034 (2)	−0.027 (3)
O4W	0.042 (2)	0.050 (2)	0.0344 (19)	−0.0087 (19)	0.0221 (18)	−0.0114 (18)
O5W	0.050 (2)	0.041 (2)	0.051 (2)	−0.0005 (19)	0.030 (2)	0.0033 (19)

Geometric parameters (Å, º)

Ba1—O3W	2.713 (4)	Ru1—Cl5	2.3755 (15)
Ba1—O1W	2.780 (4)	O1—Ru1^ii	1.7657 (4)
Ba1—O5W	2.809 (4)	O1W—H21W	0.79 (3)
Ba1—O2W	2.882 (4)	O1W—H11W	0.846 (10)
Ba1—O2W^i	2.931 (4)	O2W—Ba1^iii	2.931 (4)
Ba1—O4W	2.988 (4)	O2W—H12W	0.81 (4)
Ba1—O4W^i	3.004 (4)	O2W—H22W	0.76 (4)
Ba1—Cl2	3.1986 (12)	O3W—H13W	0.73 (5)
Ba1—Cl3	3.2882 (13)	O3W—H23W	0.78 (4)
Ru1—O1	1.7657 (4)	O4W—Ba1^iii	3.004 (4)
Ru1—Cl3	2.3394 (12)	O4W—H24W	0.85 (3)
Ru1—Cl4	2.3627 (14)	O4W—H14W	0.78 (4)
Ru1—Cl1	2.3665 (12)	O5W—H15W	0.81 (5)
Ru1—Cl2	2.3744 (12)	O5W—H25W	0.88 (5)
O3W—Ba1—O1W	72.33 (13)	Cl3—Ru1—Cl4	87.97 (4)
O3W—Ba1—O5W	68.55 (14)	O1—Ru1—Cl1	91.93 (4)
O1W—Ba1—O5W	68.89 (12)	Cl3—Ru1—Cl1	87.84 (4)
O3W—Ba1—O2W	106.46 (14)	Cl4—Ru1—Cl1	88.20 (5)
O1W—Ba1—O2W	90.31 (12)	O1—Ru1—Cl2	91.45 (4)
O5W—Ba1—O2W	159.20 (12)	Cl3—Ru1—Cl2	88.79 (4)
O3W—Ba1—O2W^i	85.88 (14)	Cl4—Ru1—Cl2	90.75 (4)
O1W—Ba1—O2W^i	141.23 (12)	Cl1—Ru1—Cl2	176.50 (4)
O5W—Ba1—O2W^i	73.44 (11)	O1—Ru1—Cl5	91.19 (13)
O2W—Ba1—O2W^i	127.12 (6)	Cl3—Ru1—Cl5	88.35 (4)
O3W—Ba1—O4W	140.66 (13)	Cl4—Ru1—Cl5	176.30 (5)
O1W—Ba1—O4W	70.02 (12)	Cl1—Ru1—Cl5	92.07 (5)
O5W—Ba1—O4W	107.09 (12)	Cl2—Ru1—Cl5	88.76 (4)
O2W—Ba1—O4W	63.18 (10)	Ru1—Cl2—Ba1	105.92 (4)
O2W^i—Ba1—O4W	131.76 (11)	Ru1—Cl3—Ba1	104.10 (4)
O3W—Ba1—O4W^i	72.37 (12)	Ru1—O1—Ru1^ii	176.9 (3)
O1W—Ba1—O4W^i	134.09 (12)	Ba1—O1W—H21W	115 (5)
O5W—Ba1—O4W^i	121.94 (11)	Ba1—O1W—H11W	119 (5)
O2W—Ba1—O4W^i	72.71 (11)	H21W—O1W—H11W	108 (4)
O2W^i—Ba1—O4W^i	62.42 (10)	Ba1—O2W—Ba1^iii	119.74 (12)
O4W—Ba1—O4W^i	130.13 (6)	Ba1—O2W—H12W	110 (5)
O3W—Ba1—Cl2	146.54 (10)	Ba1^iii—O2W—H12W	111 (5)
O1W—Ba1—Cl2	137.37 (9)	Ba1—O2W—H22W	95 (5)
O5W—Ba1—Cl2	129.21 (9)	Ba1^iii—O2W—H22W	110 (5)
O2W—Ba1—Cl2	66.31 (8)	H12W—O2W—H22W	109 (5)
O2W^i—Ba1—Cl2	75.56 (8)	Ba1—O3W—H13W	131 (6)
O4W—Ba1—Cl2	67.66 (8)	Ba1—O3W—H23W	119 (6)
O4W^i—Ba1—Cl2	74.37 (8)	H13W—O3W—H23W	108 (6)
O3W—Ba1—Cl3	133.20 (12)	Ba1—O4W—Ba1^iii	114.07 (11)
O1W—Ba1—Cl3	109.65 (9)	Ba1—O4W—H24W	108 (5)
O5W—Ba1—Cl3	69.25 (9)	Ba1^iii—O4W—H24W	111 (5)
O2W—Ba1—Cl3	120.12 (8)	Ba1—O4W—H14W	113 (5)
O2W^i—Ba1—Cl3	63.36 (7)	Ba1^iii—O4W—H14W	101 (5)
O4W—Ba1—Cl3	71.82 (8)	H24W—O4W—H14W	109 (5)
O4W^i—Ba1—Cl3	115.81 (8)	Ba1—O5W—H15W	111 (5)
Cl2—Ba1—Cl3	61.10 (3)	Ba1—O5W—H25W	130 (4)
O1—Ru1—Cl3	179.48 (13)	H15W—O5W—H25W	108 (5)
O1—Ru1—Cl4	92.49 (13)

Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+1, y, −z+3/2; (iii) −x+1/2, y−1/2, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H11W···O3W^iv	0.85 (1)	2.58 (4)	3.347 (7)	151 (6)
O2W—H12W···Cl1^v	0.82 (6)	2.36 (6)	3.176 (4)	177 (7)
O3W—H13W···Cl4^i	0.73 (7)	2.66 (6)	3.354 (6)	161 (7)
O4W—H14W···Cl4	0.78 (8)	2.62 (8)	3.395 (5)	171 (7)
O5W—H15W···O1W^iv	0.81 (9)	2.25 (9)	3.040 (9)	166 (7)
O1W—H21W···Cl2^iii	0.79 (5)	2.65 (5)	3.357 (4)	151 (6)
O1W—H21W···Cl1^vi	0.79 (5)	2.80 (6)	3.354 (5)	130 (5)
O2W—H22W···Cl5^iii	0.76 (8)	2.42 (8)	3.144 (5)	161 (7)
O3W—H23W···O5W^iv	0.79 (6)	2.20 (7)	2.932 (8)	155 (8)
O4W—H24W···Cl1^vi	0.85 (6)	2.71 (6)	3.519 (5)	160 (5)
O4W—H24W···Cl3^vi	0.85 (6)	2.81 (6)	3.324 (5)	121 (6)
O5W—H25W···Cl5^vii	0.87 (8)	2.38 (8)	3.251 (6)	173 (4)

Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (iii) −x+1/2, y−1/2, −z+3/2; (iv) −x, −y+1, −z+1; (v) x, −y+1, z+1/2; (vi) −x+1/2, −y+1/2, −z+1; (vii) −x+1/2, −y+3/2, −z+1.