supplementary materials


vn2073 scheme

Acta Cryst. (2013). E69, m404    [ doi:10.1107/S1600536813016450 ]

Chlorido[2,2'-[1,2-phenylenebis(nitrilomethanylylidyne)]diphenolato-[kappa]4O,N,N',O']manganese(III) methanol monosolvate

H. Lin, J.-G. Wang, H.-T. Shi, Q. Chen and Q.-F. Zhang

Abstract top

In the title complex, [Mn(C20H14N2O2)Cl]·CH3OH, the central MnIII atom displays a distorted square-pyramidal coordination by two N and two O atoms from the tetradentate 2,2'-[1,2-phenylenebis(nitrilomethanylylidyne)]diphenolate ligand and one chloride ligand. The MnIII atom is 0.525 (4) Å out of the square basal N2O2 least-squares plane. The complex molecule is hydrogen bonded to the methanol solvent molecule.

Comment top

The coordination chemistry of manganese complexes has been the subject of extensive investigation in the past several decades. Most of the studies have aimed to understand the role of manganese in many metallo-enzymes in terms of structure- property relationships (Dubois et al., 2003; Horner et al., 1999). Studies of high oxidation state complexes are of special importance because of their potential uses as oxidizing agents, catalysts and electro-catalysts, for the oxidation of compounds such as alcohols, esters and water (Gultneh et al., 2003). Of particular interest is the Schiff base complexes of manganese(III) which have been considered to be the simplest models for the reactivity of oxygen-evolving center (OEC) active site of mangano-enzymes (Law et al., 1998). The typical [MnIII(salen)X] (X = Cl, Br, I) complexes (salen = N,N'-bis(salicylideneiminato)ethylene) have been prepared and are soluble in aqueous and methanolic solutions (Mitra et al., 2006). Series of monochloro- and dichloro-manganese(IV) complexes along with acetatomanganese(III) complexes with the salen ligands have been previously synthesized from the mixed aqueous-ethanol or -acetonitrile solutions (Asada et al., 2000; Lenoble et al., 1998; Pecoraro & Butler, 1986). In this paper, we report the synthesis of the manganese(III) complex [MnIII(salen)Cl].CH3OH (salen = N,N'-bis(salicylideneiminato)benzene) in a mixed aqueous-methanol solution and its structural characterization involving an N2O2 Schiff base ligand.

The title complex crystallizes in the triclinic P-1 space group. The asymmetric unit of the crystal structure consists of the neutral mononuclear complex [MnIII(salen)Cl] and one methanol molecule in the lattice. A view of the complex is shown in Fig. 1. In this monomeric complex, the central manganese atom is coordinated by two nitrogen and two oxygen atoms from the salen ligand and one chloride atom. Owing to the presence of the chloride atom, the manganese atom is 0.525 (4) Å above the square basal N2O2 plane and the geometry around the metal centre may be better described as distorted square-pyramidal. The average Mn—N and Mn—O bond lengths in the title complex are 2.0992 (16) and 1.8942 (14) Å, respectively, which are compared with those in [Mn(salen)Cl(H2O)].H2O (salen = N,N'- bis(salicylideneiminato)ethylene) [av. Mn—N = 1.984 (17) Å and av. Mn—O = 1.883 (14) Å] (Panja et al., 2003), [MnCl(salen)(H2O)] (salen = 2,2'-[1,2-ethanediylbis- (nitrilomethylidyne)]-diphenolato) [av. Mn—N = 1.980 (5) Å and av. Mn—O = 1.890 (4) Å] (Martínez et al., 2002), and [Mn(L)Cl] (L = N,N'-bis{4-(diethylamino)- salicylideneiminato}-cyclohexane) [av. Mn—N = 1.986 (12) Å and av. Mn—O = 1.872 (12) Å] (Dang et al., 2005). The Mn—Cl bond length of 2.2276 (7) %A in the title complex is obviously shorter than those in [Mn(salen)Cl(H2O)].H2O (salen = N,N'-bis(salicylideneiminato)ethylene) (2.584 (12) %A) (Panja et al., 2003), [MnCl(salen)(H2O)] (salen = 2,2'-[1,2-ethanediylbis-(nitrilomethylidyne)]-diphenolato) (2.468 (2) Å) (Martínez et al., 2002), and [Mn(L)Cl] (L = N,N'-bis{4-(diethylamino)salicylideneiminato}cyclohexane) (2.386 (2) Å) (Dang et al., 2005). The basal bond angles are all approximately close to 90° [O(1)—Mn(1)—O(2), O(1)—Mn(1)—N(1) and O(2)—Mn(1)—N(2) are 91.48 (6)°, 87.99 (6)° and 87.68 (6)°, respectively] except N(1)-Mn(1)-N(2) (76.74 (6)°) which is large smaller than expected (Pecoraro & Butler, 1986). The methanol molecule takes part in one hydrogen-bond involving in H1S with the phenoxo-oxygen O1a from the next unit-cell and the distance O1a···H1S (a: x + 1, y, z) is 2.19 (2) Å (see Fig. 2).

Related literature top

For background to manganese and manganese–salen complexes, see: Law et al. (1998); Lenoble et al. (1998); Horner et al. (1999); Asada et al. (2000); Dubois et al. (2003); Gultneh et al. (2003); Mitra et al. (2006); For related structures, see: Pecoraro & Butler (1986); Dang et al. (2005); Martínez et al. (2002); Panja et al. (2003).

Experimental top

To a solution of the Schiff base ligand (H2salen) (158 mg, 0.5 mmol) in methanol (10 mL) was added Et3N (101 mg, 1.0 mmol), and then a solution of MnCl2.6H2O (117 mg, 0.5 mmol) in distilled water (5 mL) was dropwise added to the above methanol solution. The resulting solution was refluxed for 4 h, and then the mixture was filtered and the filtrate was allowed to evaporate slowly, which led to deposition of a brown solid. The solid was collected by filtration, washed with Et2O and recrystallized from CH3OH-Et2O mixture (1:1). Yield: 111 mg, 58 %. Analysis for C21H18N2O3ClMn: calcd C 57.75, H 4.15, N 6.41 %; found C 57.63, H 4.12, N 6.37 %.

Refinement top

The structure was solved by direct methods and refined by full-matrix least-squares procedure based on F2. All hydrogen atoms on the carbon atoms were placed in geometrically idealized positions and refined isotropically with a riding model for both C-sp2 [C—H = 0.93 Å and with Uiso(H) = 1.2Ueq(C)] and C-sp3 [C—H = 0.96—0.97 Å and with Uiso(H) = 1.5Ueq(C)], except the hydrogen position H1S involved in a hydrogen bond interaction and which was refined with a distance restraint.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of [MnIII(salen)Cl] (salen = N,N'-bis(salicylideneiminato)- benzene); displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of the title complex in a unit cell. Dash lines denote the intermolecular (CH3)O—H···O(salen) hydrogen bonds.
Chlorido[2,2'-[1,2-phenylenebis(nitrilomethanylylidyne)]diphenolato-κ4O,N,N',O']manganese(III) methanol monosolvate top
Crystal data top
[Mn(C20H14N2O2)Cl]·CH4OZ = 2
Mr = 436.76F(000) = 448
Triclinic, P1Dx = 1.534 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.4251 (2) ÅCell parameters from 5729 reflections
b = 9.8341 (2) Åθ = 2.4–26.8°
c = 13.3035 (3) ŵ = 0.87 mm1
α = 78.803 (1)°T = 296 K
β = 83.305 (2)°Block, pink
γ = 86.344 (2)°0.24 × 0.17 × 0.13 mm
V = 945.58 (4) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4302 independent reflections
Radiation source: fine-focus sealed tube3311 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
phi and ω scansθmax = 27.5°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 99
Tmin = 0.819, Tmax = 0.896k = 1212
17011 measured reflectionsl = 1717
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0419P)2 + 0.2015P]
where P = (Fo2 + 2Fc2)/3
4302 reflections(Δ/σ)max = 0.001
255 parametersΔρmax = 0.33 e Å3
1 restraintΔρmin = 0.40 e Å3
Crystal data top
[Mn(C20H14N2O2)Cl]·CH4Oγ = 86.344 (2)°
Mr = 436.76V = 945.58 (4) Å3
Triclinic, P1Z = 2
a = 7.4251 (2) ÅMo Kα radiation
b = 9.8341 (2) ŵ = 0.87 mm1
c = 13.3035 (3) ÅT = 296 K
α = 78.803 (1)°0.24 × 0.17 × 0.13 mm
β = 83.305 (2)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4302 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
3311 reflections with I > 2σ(I)
Tmin = 0.819, Tmax = 0.896Rint = 0.032
17011 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.035H-atom parameters constrained
wR(F2) = 0.086Δρmax = 0.33 e Å3
S = 1.02Δρmin = 0.40 e Å3
4302 reflectionsAbsolute structure: ?
255 parametersAbsolute structure parameter: ?
1 restraintRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/Ueq
Mn10.06050 (4)0.87475 (3)0.26112 (2)0.03227 (10)
Cl10.30457 (9)0.81214 (7)0.34473 (5)0.06368 (18)
N10.1304 (2)1.06118 (16)0.16224 (12)0.0368 (4)
N20.0670 (2)1.02686 (16)0.33991 (11)0.0345 (4)
O10.0801 (2)0.79008 (14)0.14311 (10)0.0475 (4)
O20.1221 (2)0.75440 (15)0.32907 (11)0.0522 (4)
C10.1710 (3)0.8242 (2)0.05065 (14)0.0388 (4)
C20.2021 (3)0.7250 (2)0.01285 (16)0.0479 (5)
H20.15880.63640.01040.057*
C30.2960 (3)0.7574 (3)0.10922 (17)0.0535 (6)
H30.31690.68970.14980.064*
C40.3601 (3)0.8889 (3)0.14702 (17)0.0537 (6)
H40.42500.90920.21190.064*
C50.3266 (3)0.9881 (2)0.08765 (16)0.0477 (5)
H50.36621.07720.11360.057*
C60.2334 (3)0.9589 (2)0.01207 (14)0.0383 (4)
C70.2019 (3)1.0706 (2)0.06718 (15)0.0394 (4)
H70.23561.15800.03200.047*
C80.1020 (3)1.18087 (19)0.20795 (14)0.0358 (4)
C90.1713 (3)1.3105 (2)0.16491 (16)0.0453 (5)
H90.24401.32280.10230.054*
C100.1317 (3)1.4201 (2)0.21548 (17)0.0485 (5)
H100.17781.50640.18670.058*
C110.0245 (3)1.4028 (2)0.30831 (18)0.0482 (5)
H110.00181.47790.34140.058*
C120.0441 (3)1.2757 (2)0.35271 (16)0.0433 (5)
H120.11571.26480.41570.052*
C130.0057 (3)1.16326 (19)0.30263 (14)0.0344 (4)
C140.1822 (3)1.0000 (2)0.42216 (14)0.0369 (4)
H140.22171.07340.45510.044*
C150.2531 (3)0.8672 (2)0.46599 (14)0.0367 (4)
C160.3650 (3)0.8553 (2)0.56071 (15)0.0427 (5)
H160.39120.93320.59060.051*
C170.4353 (3)0.7316 (2)0.60900 (16)0.0486 (5)
H170.50950.72540.67090.058*
C180.3944 (3)0.6145 (2)0.56445 (17)0.0507 (6)
H180.43840.52930.59820.061*
C190.2902 (3)0.6237 (2)0.47166 (17)0.0501 (5)
H190.26700.54490.44250.060*
C200.2181 (3)0.7492 (2)0.41977 (15)0.0395 (5)
C1S0.6113 (4)0.6064 (3)0.1772 (3)0.0922 (10)
H1S10.63770.52840.22980.138*
H1S20.51540.58470.14110.138*
H1S30.57420.68550.20810.138*
O1S0.7639 (3)0.6357 (2)0.10906 (15)0.0848 (6)
H1S0.8457 (10)0.6671 (4)0.1397 (4)0.127*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Mn10.04290 (19)0.02961 (15)0.02400 (15)0.00218 (12)0.00435 (11)0.00877 (11)
Cl10.0695 (4)0.0623 (4)0.0640 (4)0.0191 (3)0.0223 (3)0.0216 (3)
N10.0434 (9)0.0363 (8)0.0313 (8)0.0010 (7)0.0008 (7)0.0095 (7)
N20.0406 (9)0.0335 (8)0.0296 (8)0.0000 (7)0.0012 (7)0.0082 (7)
O10.0711 (10)0.0413 (8)0.0303 (7)0.0094 (7)0.0070 (7)0.0124 (6)
O20.0673 (10)0.0460 (8)0.0445 (8)0.0185 (7)0.0193 (7)0.0215 (7)
C10.0462 (12)0.0448 (11)0.0256 (9)0.0027 (9)0.0009 (8)0.0105 (8)
C20.0654 (15)0.0439 (12)0.0346 (11)0.0005 (10)0.0002 (10)0.0125 (9)
C30.0662 (15)0.0590 (14)0.0373 (11)0.0093 (12)0.0022 (10)0.0224 (11)
C40.0579 (14)0.0696 (16)0.0329 (11)0.0013 (12)0.0084 (10)0.0159 (11)
C50.0521 (13)0.0557 (13)0.0346 (11)0.0075 (10)0.0048 (9)0.0105 (10)
C60.0409 (11)0.0442 (11)0.0302 (10)0.0005 (9)0.0001 (8)0.0104 (8)
C70.0453 (12)0.0397 (10)0.0319 (10)0.0054 (9)0.0019 (8)0.0062 (8)
C80.0445 (11)0.0316 (9)0.0318 (10)0.0000 (8)0.0047 (8)0.0074 (8)
C90.0592 (14)0.0397 (11)0.0355 (11)0.0066 (10)0.0010 (10)0.0056 (9)
C100.0626 (14)0.0335 (10)0.0486 (13)0.0058 (10)0.0052 (11)0.0046 (9)
C110.0559 (14)0.0359 (11)0.0550 (13)0.0026 (10)0.0020 (11)0.0175 (10)
C120.0477 (12)0.0402 (11)0.0426 (12)0.0033 (9)0.0008 (9)0.0144 (9)
C130.0387 (11)0.0314 (9)0.0333 (10)0.0018 (8)0.0039 (8)0.0080 (8)
C140.0405 (11)0.0390 (10)0.0318 (10)0.0024 (8)0.0004 (8)0.0121 (8)
C150.0368 (11)0.0409 (10)0.0331 (10)0.0011 (8)0.0009 (8)0.0107 (8)
C160.0448 (12)0.0473 (12)0.0353 (10)0.0006 (9)0.0057 (9)0.0131 (9)
C170.0493 (13)0.0600 (14)0.0351 (11)0.0083 (11)0.0084 (9)0.0113 (10)
C180.0568 (14)0.0497 (13)0.0438 (12)0.0178 (11)0.0059 (10)0.0060 (10)
C190.0570 (14)0.0461 (12)0.0493 (13)0.0142 (10)0.0095 (11)0.0192 (10)
C200.0409 (11)0.0437 (11)0.0345 (10)0.0069 (9)0.0039 (8)0.0117 (9)
C1S0.093 (2)0.077 (2)0.100 (2)0.0166 (18)0.029 (2)0.0218 (18)
O1S0.0820 (14)0.1037 (16)0.0640 (12)0.0195 (12)0.0008 (11)0.0039 (11)
Geometric parameters (Å, º) top
Mn1—O21.8868 (14)C9—C101.377 (3)
Mn1—O11.9022 (13)C9—H90.9300
Mn1—N12.0944 (16)C10—C111.376 (3)
Mn1—N22.1047 (15)C10—H100.9300
Mn1—Cl12.2277 (7)C11—C121.377 (3)
N1—C71.302 (2)C11—H110.9300
N1—C81.420 (2)C12—C131.396 (3)
N2—C141.303 (2)C12—H120.9300
N2—C131.421 (2)C14—C151.429 (3)
O1—C11.325 (2)C14—H140.9300
O2—C201.321 (2)C15—C201.412 (3)
C1—C21.402 (3)C15—C161.415 (3)
C1—C61.411 (3)C16—C171.365 (3)
C2—C31.376 (3)C16—H160.9300
C2—H20.9300C17—C181.395 (3)
C3—C41.387 (3)C17—H170.9300
C3—H30.9300C18—C191.369 (3)
C4—C51.364 (3)C18—H180.9300
C4—H40.9300C19—C201.398 (3)
C5—C61.409 (3)C19—H190.9300
C5—H50.9300C1S—O1S1.374 (3)
C6—C71.428 (3)C1S—H1S10.9600
C7—H70.9300C1S—H1S20.9600
C8—C91.396 (3)C1S—H1S30.9600
C8—C131.398 (3)O1S—H1S0.8725
O2—Mn1—O191.47 (6)C10—C9—H9120.1
O2—Mn1—N1148.62 (7)C8—C9—H9120.1
O1—Mn1—N187.98 (6)C11—C10—C9120.50 (19)
O2—Mn1—N287.70 (6)C11—C10—H10119.8
O1—Mn1—N2148.11 (7)C9—C10—H10119.8
N1—Mn1—N276.74 (6)C10—C11—C12120.75 (19)
O2—Mn1—Cl1105.95 (6)C10—C11—H11119.6
O1—Mn1—Cl1108.96 (5)C12—C11—H11119.6
N1—Mn1—Cl1103.86 (5)C11—C12—C13119.64 (19)
N2—Mn1—Cl1101.87 (5)C11—C12—H12120.2
C7—N1—C8120.67 (16)C13—C12—H12120.2
C7—N1—Mn1124.46 (13)C12—C13—C8119.69 (17)
C8—N1—Mn1114.81 (12)C12—C13—N2125.41 (18)
C14—N2—C13120.85 (16)C8—C13—N2114.90 (16)
C14—N2—Mn1124.04 (13)N2—C14—C15125.47 (18)
C13—N2—Mn1114.86 (12)N2—C14—H14117.3
C1—O1—Mn1131.49 (12)C15—C14—H14117.3
C20—O2—Mn1130.62 (12)C20—C15—C16118.96 (18)
O1—C1—C2119.31 (18)C20—C15—C14123.61 (17)
O1—C1—C6122.27 (17)C16—C15—C14117.43 (17)
C2—C1—C6118.39 (18)C17—C16—C15121.27 (19)
C3—C2—C1120.6 (2)C17—C16—H16119.4
C3—C2—H2119.7C15—C16—H16119.4
C1—C2—H2119.7C16—C17—C18119.27 (19)
C2—C3—C4121.3 (2)C16—C17—H17120.4
C2—C3—H3119.4C18—C17—H17120.4
C4—C3—H3119.4C19—C18—C17120.7 (2)
C5—C4—C3119.0 (2)C19—C18—H18119.6
C5—C4—H4120.5C17—C18—H18119.6
C3—C4—H4120.5C18—C19—C20121.3 (2)
C4—C5—C6121.6 (2)C18—C19—H19119.3
C4—C5—H5119.2C20—C19—H19119.3
C6—C5—H5119.2O2—C20—C19119.40 (18)
C5—C6—C1119.06 (18)O2—C20—C15122.20 (17)
C5—C6—C7117.27 (18)C19—C20—C15118.39 (18)
C1—C6—C7123.63 (17)O1S—C1S—H1S1109.5
N1—C7—C6125.92 (18)O1S—C1S—H1S2109.5
N1—C7—H7117.0H1S1—C1S—H1S2109.5
C6—C7—H7117.0O1S—C1S—H1S3109.5
C9—C8—C13119.60 (17)H1S1—C1S—H1S3109.5
C9—C8—N1124.94 (18)H1S2—C1S—H1S3109.5
C13—C8—N1115.45 (16)C1S—O1S—H1S109.5
C10—C9—C8119.82 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1S—H1S···O1i0.872.192.999 (3)154
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formula[Mn(C20H14N2O2)Cl]·CH4O
Mr436.76
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)7.4251 (2), 9.8341 (2), 13.3035 (3)
α, β, γ (°)78.803 (1), 83.305 (2), 86.344 (2)
V3)945.58 (4)
Z2
Radiation typeMo Kα
µ (mm1)0.87
Crystal size (mm)0.24 × 0.17 × 0.13
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.819, 0.896
No. of measured, independent and
observed [I > 2σ(I)] reflections
17011, 4302, 3311
Rint0.032
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.086, 1.02
No. of reflections4302
No. of parameters255
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.33, 0.40

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1S—H1S···O1i0.872.192.999 (3)153.7
Symmetry code: (i) x+1, y, z.
Acknowledgements top

This project was supported by the Natural Science Foundation of China (90922008).

references
References top

Asada, H., Fujiwara, M. & Matsushita, T. (2000). Polyhedron, 19, 2039–2048.

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