supplementary materials


Acta Cryst. (2009). E65, m1259-m1260    [ doi:10.1107/S1600536809038732 ]

[1,3-Bis(2-ethoxyphenyl)triazenido]bromidomercury(II)

M. K. Rofouei, A. Beiza and J. Attar Gharamaleki

Abstract top

To the central atom of the title compound, [HgBr(C16H18N3O2)], is attached one bromide ion and a 1,3-bis(2-ethoxyphenyl)triazenide ligand through one O and two N atoms, forming a distorted square-planar geometry around the HgII atom. The mononuclear complexes are linked into centrosymmetric dimers by non-classical intermolecular C-H...N hydrogen bonds and by weak Hg-[eta]3-arene [pi]-interactions [mean distance = 3.434 (3) Å]. The resulting dimeric units are assembled into zigzag chains by translation along the crystallographic c axis through secondary C-H...[pi] edge-to-face benzene ring interactions.

Comment top

Transition metal complexes containing 1,3-diaryltriazenide ligands have been the object of numerous structural studies in the past few years because of their diverse range of coordination geometries. The uncoordinated –NN–N– compounds commonly adopt a trans configuration in the ground state. As ligands they exhibit versatile coordination geometries: with single or twofold nitrogen chains, neutral or anionic (triazenides) donor sets; they can be monodentate, (N1, N3)-chelating towards one metal atom or (N1, N3)-bridging over two metal atoms (Moore & Robinson, 1986), and they show a remarkable ability to support the stereochemical requisites of a wide variety of transition metal complexes (Hörner et al., 2002, 2004). In these compounds, secondary bonds, or interactions such as hydrogen bonds and metal π-aryl interactions, can play an important role in their structures (Vrieze & Van Koten, 1987; Hörner et al., 2006). We have previously reported the synthesis of the ligands, 1,3-bis(2-methoxyphenyl)]triazene (Rofouei et al., 2006), [1,3-bis(2-ethoxyphenyl)]triazene (Rofouei, Melardi, Salemi et al., 2009), and [1,3-bis(2-cyanophenyl)]triazene (Melardi et al., 2008). Representative metal complexes include the HgII complex with [1,3-bis(2-methoxyphenyl)]triazene by using HgCl2 (Melardi et al., 2007), HgBr2 (Hematyar & Rofouei 2008), Hg(CH3COO)2 and Hg(SCN)2 (Rofouei, Hematyar et al., 2009) salts as starting materials. In addition, Ag(I) and Cd(II) complexes with this ligand are known (Payehghadr et al., 2007; Rofouei, Melardi, Khalili Ghaydari et al., 2009). More recently, a HgII complex with [1,3-bis(2-ethoxyphenyl)]triazene as ligand was reported in which HgCl2 was used as the starting salt (Melardi et al., 2009). In this paper, a HgII complex using HgBr2 as a starting material is reported. It is isomorphous to the latter chloride complex.

The molecular structure of HgBr(C16H18N3O2) is presented in Fig. 1. The HgII atom is coordinated by one triazenide and one bromide ion. The 1,3-bis(2-ethoxyphenyl)triazenide is coordinated to the central atom through two N atoms [Hg1–N1 = 2.086 (3) Å and Hg1–N3 = 2.660 (3) Å] and one O atom [Hg1–O1 = 2.722 (3) Å] at a relatively long distance. The Hg1–Br1 distance of 2.4014 (4) Å is shorter than the corresponding distance in 1,3-bis(2-methoxyphenyl) with Hg1–Br1 = 2.5175 (11) Å (Hematyar & Rofouei, 2008). The Hg–Cl, Hg–O and Hg–N bonds distances in the isomorphous chloride, HgCl(C16H18N3O2), are 2.284 (8), 2.721 (2), 2.074 (2) and 2.674 (2) Å, respectively. The atoms of the ligand and the bromide ion generate a plane (maximum deviation from coplanarity of 0.037 Å).

In the title compound, the monomeric HgBr(C16H18N3O2) moieties are linked to pairs through non-classical C13–H13B···N2 hydrogen bond (C13···N2 = 3.496 (5) Å and <C13–H13B···N2 = 151 °, symmetry code (-x, 2 - y, -z). Also, weak Hg-η3-arene π-interactions (mean distance of 3.434 (3) Å) are present between these dimers. The secondary Hg-η3-arene π-interactions involving three carbon atoms of the C1–C6 phenyl ring. These metal-π interactions involve the Hg1 atom and C4 [3.461 (5) Å], C5 [3.254 (5) Å] and C6 [3.515 (5) Å] atoms with related symmetry code (-x, 2 - y, -z) (Fig. 2). The resulted dimeric units are assembled into zigzag chains by translation along the crystallographic c axis through secondary C–H···π stacking interactions. These edge-to-face interactions are present between CH group of phenyl rings and aromatic rings with H···π distances of 2.72 and 2.85 Å for C13–H13A···Cg1 [symmetry code: 1/2 - x, -1/2 + y, 1/2 - z] and C12–H12···Cg1 [symmetry code: -x, 1 - y, -z], respectively in which Cg1 is the centroid for C7—C12 aromatic ring (Fig. 3). The sum of the weak non-covalent interactions seems to play an important role in the crystal packing. The unit cell packing diagram of the title compound is shown in Fig. 4.

Related literature top

For aryl triazenes, their structural properties and metal complexes see: Vrieze & Van Koten (1987); Hörner et al. (2002, 2004, 2006). For the different coordination modes of the triazenide ligand, see: Moore & Robinson (1986). For the synthesis and molecular structure of similar structures with cyano, methoxy and ethoxy groups, see: Melardi et al. (2008); Rofouei et al. (2006); Rofouei, Melardi, Salemi et al. (2009). For the synthesis and crystal structures of HgII complexes with [1,3-bis(2-methoxyphenyl)]triazene by using HgCl2, HgBr2, Hg(CH3COO)2 and Hg(SCN)2 salts as starting materials, see: Melardi et al. (2007); Hematyar & Rofouei (2008); Rofouei, Hematyar et al. (2009). For the synthesis and crystal structures of cadmium(II) and silver(I) complexes with 1,3-bis(2-methoxyphenyl)triazene, see: Rofouei, Melardi, Khalili Ghaydari et al. (2009) and Payehghadr et al. (2007), respectively. For the synthesis and characterization of an isomorphous HgII structure with [1,3-bis(2-ethoxyphenyl)]triazene by using HgCl2 instead of HgBr2, see: Melardi et al. (2009). Cg1 is the centroid of the C7–C12 aromatic ring

Experimental top

A methanol solution of 1,3-bis(2-ethoxyphenyl)triazene (0.2853 g, 1 mmol) was added to a methanol solution of mercury(II) bromide (0.3604 g, 1 mmol). After mixing for 1 h at room temperature, an orange solid was readily precipitated out. It was then filtered off, washed with methanol and dried in vacuum. The orange crude material was dissolved in 10 ml of THF, and placed in a freezer without covering. After two weeks beautiful orange and air-stable crystals of the title complex were obtained by slow evaporation of the solvent.

Refinement top

Positions of the H(C) were calculated from geometry with C—H = 0.95 - 0.99 Å. All hydrogen atoms were refined by use of a riding model with Uiso(H) parameters equal to 1.5 Ueq(C) for methyl groups and to 1.2 Ueq(C) for other carbon atoms where Ueq(C) are the equivalent isotropic thermal parameters of the atoms to which the corresponding H atoms are bonded.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006), PLATON (Spek, 2009) and SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, with ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Non-classical C13–H13B···N2 hydrogen bond with H13B···N2 distance of 2.60 Å and weak Hg-η3-arene π-interactions (mean distance of 3.434 (3) Å) between dimers. The secondary Hg-η3-arene π-interactions involve three carbon atoms of the C1–C6 phenyl ring.
[Figure 3] Fig. 3. C–H···π stacking interactions between CH group of phenyl rings and aromatic rings with H···π distances of 2.72 and 2.85 Å for C13–H13A···Cg1 and C12–H12···Cg1 (Cg1 is the centroid for the C7—C12 aromatic ring).
[Figure 4] Fig. 4. The packing diagram of the title compound.
[1,3-Bis(2-ethoxyphenyl)triazenido]bromidomercury(II) top
Crystal data top
[HgBr(C16H18N3O2)]F(000) = 1064
Mr = 564.83Dx = 2.217 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4844 reflections
a = 10.2359 (7) Åθ = 2.3–29.5°
b = 7.4659 (5) ŵ = 11.47 mm1
c = 22.4123 (14) ÅT = 100 K
β = 98.860 (6)°Plate, orange
V = 1692.32 (19) Å30.28 × 0.12 × 0.03 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
4943 independent reflections
Radiation source: fine-focus sealed tube4081 reflections with I > 2σ(I)
graphiteRint = 0.061
ω scansθmax = 30.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1998)
h = 1414
Tmin = 0.221, Tmax = 0.709k = 1010
20759 measured reflectionsl = 3131
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.062H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.01P)2]
where P = (Fo2 + 2Fc2)/3
4943 reflections(Δ/σ)max = 0.001
210 parametersΔρmax = 1.33 e Å3
0 restraintsΔρmin = 1.43 e Å3
Crystal data top
[HgBr(C16H18N3O2)]V = 1692.32 (19) Å3
Mr = 564.83Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.2359 (7) ŵ = 11.47 mm1
b = 7.4659 (5) ÅT = 100 K
c = 22.4123 (14) Å0.28 × 0.12 × 0.03 mm
β = 98.860 (6)°
Data collection top
Bruker APEXII CCD
diffractometer
4943 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1998)
4081 reflections with I > 2σ(I)
Tmin = 0.221, Tmax = 0.709Rint = 0.061
20759 measured reflectionsθmax = 30.0°
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.062Δρmax = 1.33 e Å3
S = 1.00Δρmin = 1.43 e Å3
4943 reflectionsAbsolute structure: ?
210 parametersFlack parameter: ?
0 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. The maximum and minimum difference map peaks are within 1.21 Å of Hg1.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Hg10.152069 (14)0.681795 (19)0.053806 (7)0.01739 (5)
Br10.36007 (4)0.63210 (6)0.08813 (2)0.02803 (10)
O10.1764 (2)0.8602 (3)0.05325 (12)0.0160 (5)
O20.0190 (3)0.4368 (3)0.20087 (13)0.0175 (6)
N10.0246 (3)0.7115 (4)0.01922 (15)0.0148 (6)
N20.1262 (3)0.6390 (4)0.05569 (15)0.0140 (6)
N30.0888 (3)0.5769 (4)0.10309 (15)0.0147 (6)
C10.0555 (3)0.8727 (5)0.07197 (17)0.0127 (7)
C20.0503 (4)0.7918 (4)0.03385 (17)0.0133 (7)
C30.1769 (4)0.7992 (5)0.05036 (18)0.0170 (8)
H30.24930.74410.02540.020*
C40.1972 (4)0.8862 (5)0.1028 (2)0.0202 (8)
H40.28340.89060.11360.024*
C50.0928 (4)0.9665 (5)0.13943 (18)0.0182 (8)
H50.10731.02700.17510.022*
C60.0331 (4)0.9589 (5)0.12414 (18)0.0168 (8)
H60.10481.01340.14970.020*
C70.1494 (3)0.4203 (5)0.19634 (18)0.0143 (7)
C80.1896 (3)0.4974 (5)0.14479 (17)0.0136 (7)
C90.3235 (4)0.4931 (5)0.13872 (18)0.0172 (8)
H90.35140.54750.10450.021*
C100.4158 (4)0.4114 (5)0.18149 (19)0.0187 (8)
H100.50660.41050.17700.022*
C110.3744 (4)0.3301 (5)0.23141 (19)0.0183 (8)
H110.43710.27160.26060.022*
C120.2414 (4)0.3343 (5)0.23868 (19)0.0173 (8)
H120.21390.27810.27270.021*
C130.2862 (4)0.9515 (5)0.08961 (18)0.0174 (8)
H13A0.30020.90340.13130.021*
H13B0.26781.08140.09140.021*
C140.4070 (4)0.9196 (6)0.0602 (2)0.0233 (9)
H14A0.48090.99070.08090.035*
H14B0.38850.95520.01770.035*
H14C0.43030.79220.06300.035*
C150.0256 (4)0.3651 (5)0.25327 (19)0.0213 (8)
H15A0.02510.41790.29020.026*
H15B0.01320.23360.25480.026*
C160.1692 (4)0.4104 (6)0.2491 (2)0.0272 (10)
H16A0.20480.35430.28280.041*
H16B0.21730.36590.21080.041*
H16C0.17950.54060.25110.041*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Hg10.01495 (7)0.01991 (8)0.01826 (8)0.00083 (5)0.00561 (5)0.00169 (6)
Br10.01972 (19)0.0300 (2)0.0374 (3)0.00079 (16)0.01402 (18)0.00757 (19)
O10.0130 (12)0.0221 (13)0.0132 (14)0.0018 (10)0.0027 (10)0.0021 (11)
O20.0165 (13)0.0211 (13)0.0156 (14)0.0003 (10)0.0042 (11)0.0040 (11)
N10.0134 (14)0.0167 (15)0.0134 (16)0.0014 (11)0.0006 (12)0.0011 (12)
N20.0169 (15)0.0129 (14)0.0117 (16)0.0016 (11)0.0006 (12)0.0013 (12)
N30.0156 (15)0.0143 (14)0.0138 (16)0.0030 (11)0.0010 (12)0.0007 (12)
C10.0149 (17)0.0127 (15)0.0103 (17)0.0005 (13)0.0017 (14)0.0027 (14)
C20.0158 (17)0.0123 (16)0.0123 (18)0.0007 (12)0.0043 (14)0.0009 (13)
C30.0142 (17)0.0181 (18)0.019 (2)0.0015 (13)0.0032 (15)0.0000 (15)
C40.0159 (18)0.0242 (19)0.022 (2)0.0039 (15)0.0085 (16)0.0017 (17)
C50.0197 (19)0.0212 (19)0.0149 (19)0.0034 (15)0.0061 (15)0.0005 (16)
C60.0183 (18)0.0148 (17)0.017 (2)0.0002 (14)0.0017 (15)0.0008 (15)
C70.0141 (17)0.0119 (16)0.0168 (19)0.0004 (13)0.0028 (14)0.0005 (14)
C80.0170 (17)0.0123 (16)0.0110 (18)0.0001 (13)0.0007 (14)0.0020 (14)
C90.0208 (19)0.0146 (17)0.017 (2)0.0034 (14)0.0041 (15)0.0011 (15)
C100.0171 (18)0.0187 (19)0.019 (2)0.0005 (14)0.0001 (15)0.0015 (16)
C110.0183 (18)0.0173 (17)0.017 (2)0.0004 (14)0.0035 (15)0.0022 (16)
C120.0215 (18)0.0131 (17)0.0167 (19)0.0001 (14)0.0018 (15)0.0004 (15)
C130.0146 (17)0.0189 (18)0.017 (2)0.0005 (14)0.0018 (15)0.0005 (16)
C140.0162 (19)0.030 (2)0.023 (2)0.0012 (16)0.0029 (16)0.0019 (18)
C150.029 (2)0.0205 (19)0.015 (2)0.0008 (16)0.0069 (17)0.0025 (16)
C160.029 (2)0.029 (2)0.028 (3)0.0044 (17)0.0154 (19)0.0074 (19)
Geometric parameters (Å, °) top
Hg1—N12.086 (3)C7—C81.408 (5)
Hg1—Br12.4014 (4)C8—C91.398 (5)
Hg1—N32.660 (3)C9—C101.380 (5)
O1—C11.370 (4)C9—H90.9500
O1—C131.452 (4)C10—C111.395 (6)
O2—C71.359 (4)C10—H100.9500
O2—C151.428 (5)C11—C121.396 (5)
N1—N21.334 (4)C11—H110.9500
N1—C21.393 (5)C12—H120.9500
N2—N31.271 (4)C13—C141.507 (5)
N3—C81.412 (5)C13—H13A0.9900
C1—C61.384 (5)C13—H13B0.9900
C1—C21.408 (5)C14—H14A0.9800
C2—C31.403 (5)C14—H14B0.9800
C3—C41.386 (6)C14—H14C0.9800
C3—H30.9500C15—C161.497 (6)
C4—C51.381 (6)C15—H15A0.9900
C4—H40.9500C15—H15B0.9900
C5—C61.385 (5)C16—H16A0.9800
C5—H50.9500C16—H16B0.9800
C6—H60.9500C16—H16C0.9800
C7—C121.387 (5)
N1—Hg1—Br1175.94 (9)C10—C9—C8121.3 (4)
N1—Hg1—N352.01 (11)C10—C9—H9119.4
Br1—Hg1—N3129.22 (7)C8—C9—H9119.4
C1—O1—C13117.0 (3)C9—C10—C11119.3 (4)
C7—O2—C15118.0 (3)C9—C10—H10120.4
N2—N1—C2117.8 (3)C11—C10—H10120.4
N2—N1—Hg1111.6 (2)C10—C11—C12120.4 (4)
C2—N1—Hg1130.7 (2)C10—C11—H11119.8
N3—N2—N1110.7 (3)C12—C11—H11119.8
N2—N3—C8115.1 (3)C7—C12—C11120.1 (4)
N2—N3—Hg185.7 (2)C7—C12—H12119.9
C8—N3—Hg1159.2 (3)C11—C12—H12119.9
O1—C1—C6124.4 (3)O1—C13—C14107.3 (3)
O1—C1—C2115.6 (3)O1—C13—H13A110.3
C6—C1—C2120.0 (3)C14—C13—H13A110.3
N1—C2—C3123.1 (3)O1—C13—H13B110.3
N1—C2—C1118.3 (3)C14—C13—H13B110.3
C3—C2—C1118.6 (3)H13A—C13—H13B108.5
C4—C3—C2120.5 (4)C13—C14—H14A109.5
C4—C3—H3119.7C13—C14—H14B109.5
C2—C3—H3119.7H14A—C14—H14B109.5
C5—C4—C3120.3 (4)C13—C14—H14C109.5
C5—C4—H4119.9H14A—C14—H14C109.5
C3—C4—H4119.9H14B—C14—H14C109.5
C4—C5—C6120.0 (4)O2—C15—C16107.5 (3)
C4—C5—H5120.0O2—C15—H15A110.2
C6—C5—H5120.0C16—C15—H15A110.2
C1—C6—C5120.6 (4)O2—C15—H15B110.2
C1—C6—H6119.7C16—C15—H15B110.2
C5—C6—H6119.7H15A—C15—H15B108.5
O2—C7—C12124.2 (4)C15—C16—H16A109.5
O2—C7—C8116.0 (3)C15—C16—H16B109.5
C12—C7—C8119.8 (3)H16A—C16—H16B109.5
C9—C8—C7119.0 (3)C15—C16—H16C109.5
C9—C8—N3124.9 (3)H16A—C16—H16C109.5
C7—C8—N3116.0 (3)H16B—C16—H16C109.5
N3—Hg1—N1—N21.4 (2)C3—C4—C5—C60.6 (6)
N3—Hg1—N1—C2178.7 (4)O1—C1—C6—C5179.5 (3)
C2—N1—N2—N3177.6 (3)C2—C1—C6—C50.1 (5)
Hg1—N1—N2—N32.5 (3)C4—C5—C6—C10.6 (6)
N1—N2—N3—C8179.9 (3)C15—O2—C7—C121.7 (5)
N1—N2—N3—Hg11.8 (3)C15—O2—C7—C8178.3 (3)
N1—Hg1—N3—N21.37 (19)O2—C7—C8—C9176.9 (3)
Br1—Hg1—N3—N2173.68 (16)C12—C7—C8—C93.1 (5)
N1—Hg1—N3—C8177.1 (7)O2—C7—C8—N32.1 (5)
Br1—Hg1—N3—C82.1 (7)C12—C7—C8—N3177.9 (3)
C13—O1—C1—C63.0 (5)N2—N3—C8—C93.9 (5)
C13—O1—C1—C2176.4 (3)Hg1—N3—C8—C9179.2 (5)
N2—N1—C2—C30.1 (5)N2—N3—C8—C7177.2 (3)
Hg1—N1—C2—C3179.7 (3)Hg1—N3—C8—C71.9 (8)
N2—N1—C2—C1178.4 (3)C7—C8—C9—C101.5 (5)
Hg1—N1—C2—C11.7 (5)N3—C8—C9—C10179.6 (3)
O1—C1—C2—N11.5 (5)C8—C9—C10—C110.6 (6)
C6—C1—C2—N1177.9 (3)C9—C10—C11—C121.2 (6)
O1—C1—C2—C3179.8 (3)O2—C7—C12—C11177.5 (3)
C6—C1—C2—C30.7 (5)C8—C7—C12—C112.5 (5)
N1—C2—C3—C4177.8 (3)C10—C11—C12—C70.3 (6)
C1—C2—C3—C40.7 (5)C1—O1—C13—C14179.7 (3)
C2—C3—C4—C50.1 (6)C7—O2—C15—C16176.5 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C13—H13B···N2i0.992.603.496 (5)151
C12—H12···Cg1ii0.952.853.559 (4)132
C13—H13A···Cg1iii0.992.723.523 (4)139
Symmetry codes: (i) −x, −y+2, −z; (ii) −x+1/2, y−1/2, −z+1/2; (iii) −x, −y+1, −z.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
C13—H13B···N2i0.992.603.496 (5)151
C12—H12···Cg1ii0.952.853.559 (4)132
C13—H13A···Cg1iii0.992.723.523 (4)139
Symmetry codes: (i) −x, −y+2, −z; (ii) −x+1/2, y−1/2, −z+1/2; (iii) −x, −y+1, −z.
references
References top

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