Penta­aqua­tri-μ3-hydroxido-tris­(imino­diacetato)-μ3-oxido-tetra­hedro-calcium(II)tricobalt(III) 2.54-hydrate

Ama, T.; Yonemura, T.; Morita, S.; Yamaguchi, M.

doi:10.1107/S1600536810010998

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 4| April 2010| Pages m483-m484

doi:10.1107/S1600536810010998

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Pentaaquatri-μ₃-hydroxido-tris(iminodiacetato)-μ₃-oxido-tetrahedro-calcium(II)tricobalt(III) 2.54-hydrate

Tomoharu Ama,^a ^* Toshiaki Yonemura,^a Shogo Morita ^a and Masanori Yamaguchi ^a

^aDepartment of Chemistry, Faculty of Science, Kochi University, Akebono-cho 2-5-1, Kochi 780-8520, Japan
^*Correspondence e-mail: tomama@cc.kochi-u.ac.jp

(Received 18 March 2010; accepted 24 March 2010; online 31 March 2010)

In the title compound, [CaCo₃(C₄H₅NO₄)₃(OH)₃O(H₂O)₅]·2.54H₂O, the Co atom is octahedrally coordinated by one iminodiacetate (ida) dianion as a facial O,N,O′-tridentate ligand, two μ₃-OH groups and one μ₃-O ligand, forming an partial Co₃O₄ cubane cluster. This unit coordinates to a Ca^II cation in an O,O′,O′′-tridentate fashion, generating a distorted CaCo₃O₄ cubane-type cluster. The Ca—μ₃-O distances [2.429 (5)–2.572 (6) Å] are much longer than the Co—μ₃—O bonds [1.895 (5)–1.941 (5) Å]. The Ca^II cation is also coordinated by five water molecules with Ca—O distances in the range 2.355 (6)–2.543 (6) Å. There are three additional uncoordinated water molecules in the asymmetric unit, the occupancy of which refined to 0.54 (3). In H₂O (or D₂O), the title complex hydrolyses to Ca²⁺_aq cations and [Co₃(ida)₃(μ₂-OH)₃(μ₃-O)]²⁻ anions.

Related literature

For the synthesis and chemistry of partial Co₃O₄ cubane clusters, see: Ama et al. (1997 , 2000 , 2001 , 2006 ). For the chemistry and structure of CaMn₄O₄ clusters in the OEC (oxygen evolution center) of plants, see: Barber & Murray (2008 ); Rappaport & Diner (2008 ); Sauer et al. (2008 ); Yocum (2008 ). For a related structure, see: Ama et al. (1995 ).

Experimental

Crystal data

[CaCo₃(C₄H₅NO₄)₃(OH)₃O(H₂O)₅]·2.54H₂O
M_r = 812.92
Triclinic, $[P \overline 1]$
a = 10.474 (3) Å
b = 11.303 (7) Å
c = 12.588 (5) Å
α = 75.88 (4)°
β = 100.92 (3)°
γ = 104.58 (3)°
V = 1385.6 (10) Å³
Z = 2
Mo Kα radiation
μ = 2.06 mm⁻¹
T = 296 K
0.40 × 0.40 × 0.05 mm

Data collection

Rigaku AFC-7S diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.673, T_max = 0.902
6713 measured reflections
6360 independent reflections
3290 reflections with F² > 2σ(F²)
R_int = 0.076
3 standard reflections every 150 reflections intensity decay: 4.8%

Refinement

R[F² > 2σ(F²)] = 0.060
wR(F²) = 0.207
S = 1.00
6360 reflections
389 parameters
H-atom parameters constrained
Δρ_max = 1.17 e Å⁻³
Δρ_min = −1.13 e Å⁻³

Table 1
Selected bond lengths (Å)

Co1—O1	1.877 (5)
Co1—O2	1.903 (5)
Co1—O4	1.941 (5)
Co2—O1	1.888 (4)
Co2—O2	1.907 (5)
Co2—O3	1.895 (5)
Co3—O1	1.866 (5)
Co3—O3	1.915 (5)
Co3—O4	1.921 (5)
Ca1—O2	2.572 (6)
Ca1—O3	2.527 (6)
Ca1—O4	2.429 (5)
Ca1—O17	2.355 (6)
Ca1—O18	2.411 (6)
Ca1—O19	2.543 (6)
Ca1—O20	2.406 (6)
Ca1—O21	2.471 (8)

Data collection: WinAFC (Rigaku/MSC, 2000 ); cell refinement: WinAFC; data reduction: CrystalStructure (Rigaku/MSC, 2007 ); program(s) used to solve structure: DIRDIF99 (Beurskens et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2007).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810010998/sj2753sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810010998/sj2753Isup2.hkl

checkCIF report

Comment top

We have previously reported on the structures of some [Co₃(L)₃(µ₂-OH)₃(µ₃-O)]ⁿ⁺ (L: tridentate ligand) complexes which form incomplete cubane Co₃O₄ clusters (Ama et al., 1997, 2000,2001, 2006). While many such cationic [Co₃(L)₃(µ₂-OH)₃(µ₃-O)]ⁿ⁺ complexes are known, we could find no mention of an anionic complex in our survey of the literature. The title compound was formed during an attempt to prepare the anionic complex [Co₃(ida)₃(µ₂-OH)₃(µ₃-O)]^2-.

Investigations of the CaMn₃O₄ cluster are important to gain an understanding of the chemistry of O₂ evolution centers (OEC) in plants (Yocum, 2008; Sauer et al., 2008; Barber & Murray, 2008; Rappaport & Diner, 2008). The Mn clusters in the OEC are of interest due to their unique structure, photoreaction mechanisms, and redox chemistry. Moreover, as the covalent radius of Co (1.33 Å) is similar to that of Mn (1.35 Å), we were interested in the preparation of the cobalt analogue, CaCo₃O₄, as a model of OEC.

In the title complex, each Co atom is coordinated by one ida (iminodiacetato) molecule which acts as a facial tridentate (O,N,O') ligand, two µ₂-OH groups and one µ₃-O ligand, forming a Co₃O₄ cluster. This cluster further coordinates to Ca^II in a tridentate manner generating a distorted CaCo₃O₄ cubane-type cluster. The µ₂-O—Co distances are 1.895 (5) - 1.941 (5)Å and the Co—µ₂-O—Co' angles are 94.5 (2) – 95.8 (2)°. In the T1 isomer (Ama et al., 1995) of [Co₃(edma)₃(µ₂-OH)₃(µ₃-O)]⁺ (edma: ethylenediaminemonoacetato), the corresponding distances and angles are 1.899 (3) -1.923 (2)Å and 95.0 (1) - 96.2 (1)°. Hence the structure of the Co₃O₄ cluster in the title compound resembles that of [Co₃(edma)₃(µ₂-OH)₃(µ₃-O)]⁺ cation. As the Ca²⁺ cation is coordinated by the three µ₃-OH ligands of the Co₃O₄ cluster, the CaCo₃O₄ cluster can be considered to be a distorted cubane cluster. The Ca—µ₃-O distances (2.429 (5) – 2.572 (6) Å) are much longer than Co—µ₃-O (1.895 (5) - 1.921 (5) Å). The µ₃-O—Ca—µ₃-O' angles (59.84 (16) - 63.09 (16)) are smaller than those involving cobalt, µ₃-O—Co—µ₃-O' (84.0 (2) - 85.6 (2)°) and Co—µ₃-O—Co' (94.5 (2) - 95.8 (2)) in the Co₃O₄ cluster. There are three additional uncoordinated water molecules in the asymmetric unit, the occupancy of one of these solvates that has the largest U_eq value refines to 0.54 (3).

Related literature top

For the synthesis and chemistry of partial Co₃O₄ cubane clusters, see: Ama et al. (1997, 2000, 2001, 2006). For the chemistry and structure of CaMn₄O₄ clusters in the OEC (oxygen evolution center) of plants, see: Barber & Murray (2008); Rappaport & Diner (2008); Sauer et al. (2008); Yocum (2008). For a related structure, see: Ama et al. (1995).

Experimental top

To a suspension of 7.0 g of KHCO₃ in 10 cm³ of water, a solution 2.38 g of cobalt(II) chloride hexahydrate and 4 cm³ of 30% H₂O₂ in 10 cm³ of water was added dropwise with stirring at below 0° C. After the solution was stirred for 15 min, 10 cm³ of H₂O containing 1.3 g of H₂ida was added and then stirred overnight. The solution was acidified to pH 1.0 with 30% HClO₄, stirred for 30 min, pH adjusted to 8.3 with 2 mol dm^-3 KOH aqueous solution and then stirred for 2.5 h at 45°C. Filtering off the insoluble white-brown precipitate, the filtrate was loaded onto a QAE-Sephadex column (Cl^- form). The adsorbed band was developed with 0.2 mol dm^-3 KCl Solution. The eluate from the fifth brown band was collected and concentrated to a small volume and then methanol was added to deposit KCl. After removing the KCl by filtration, potassium salt (K₂[Co₃(ida)₃(µ₂-OH)₃(µ₃-O)] 3.25 H₂O) was obtained by standing the filtrate in a refrigerator. Yield: 76 mg. (Anal. Found: C, 18.45; H, 3.21; N, 5.34%. Calcd for C₁₂H_24.5N₃O_19.25K₂Co₃ (K₂[Co₃(ida)₃(µ₂-OH)(µ₃-O)] 3.25 H₂O): C, 18.62; H, 3.19; N, 5.43%. This potassium salt was dissolved in a small amount of water, which was loaded to a QAE-Sephadex column (Cl^- form; ø 6.5 cm × 3.5 cm) and then eluted with 500 cm³ of water to remove the K⁺ ion in the solution. The adsorbed brown band was eluted out with 0.5 mol dm^-3 of CaCl₂. The eluted solution was concentrated to a few cm³ and then ethanol and diethylether were added. As the solution was separated into a brown and an uncolored layers, the colorless layer was removed by decantation. After these procedures were repeated several times, a large amount of ethanol was added and the solution allowed to stand overnight at room temperature. The resulting brown precipitate was collected and washed with ethanol. This crude solid was recrystallized from water by adding ethanol. Anal. Found: C, 17.84; H, 4.04; N, 5.11%. Calcd for C₁₂H_33.08N₃O_23.54CaCo₃ ([Ca(H₂O)₅Co₃(ida)₃(µ-OH)₃(µ₃-O)] 2.54 H₂O): C, 17.73; H, 4.09; N, 5.17%. ¹H NMR: (δ=4.22 and 3.24ppm; J_gem=17.6 Hz) and (δ=4.03 and 3.24ppm; J_gem=17.2 Hz).

Computing details top

Data collection: WinAFC (Rigaku/MSC, 2000); cell refinement: WinAFC (Rigaku/MSC, 2000); data reduction: CrystalStructure (Rigaku/MSC, 2007); program(s) used to solve structure: DIRDIF99 (Beurskens et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2007).

Figures top

Fig. 1. The asymmetric unit of the title compound showing the atom-labeling scheme and with 50% probability displacement ellipsoids.

Pentaaquatri-µ₃-hydroxido-tris(iminodiacetato)-µ₃-oxido- tetrahedro-calcium(II)tricobalt(III) 2.54-hydrate top

Crystal data top

[CaCo₃(C₄H₅NO₄)₃(OH)₃O(H₂O)₅]·2.54H₂O	Z = 2
M_r = 812.92	F(000) = 830.80
Triclinic, P1	D_x = 1.948 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71069 Å
a = 10.474 (3) Å	Cell parameters from 12 reflections
b = 11.303 (7) Å	θ = 15.1–15.8°
c = 12.588 (5) Å	µ = 2.06 mm⁻¹
α = 75.88 (4)°	T = 296 K
β = 100.92 (3)°	Plate, brown
γ = 104.58 (3)°	0.40 × 0.40 × 0.05 mm
V = 1385.6 (10) Å³

Data collection top

Rigaku AFC-7S diffractometer	R_int = 0.076
ω–2θ scans	θ_max = 27.5°
Absorption correction: ψ scan (North et al., 1968)	h = 0→13
T_min = 0.673, T_max = 0.902	k = −14→14
6713 measured reflections	l = −16→16
6360 independent reflections	3 standard reflections every 150 reflections
3290 reflections with F² > 2σ(F²)	intensity decay: 4.8%

Refinement top

Refinement on F²	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.060	w = 1/[σ²(F_o²) + (0.1052P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.207	(Δ/σ)_max < 0.0001
S = 1.00	Δρ_max = 1.17 e Å⁻³
6360 reflections	Δρ_min = −1.13 e Å⁻³
389 parameters

Crystal data top

[CaCo₃(C₄H₅NO₄)₃(OH)₃O(H₂O)₅]·2.54H₂O	γ = 104.58 (3)°
M_r = 812.92	V = 1385.6 (10) Å³
Triclinic, P1	Z = 2
a = 10.474 (3) Å	Mo Kα radiation
b = 11.303 (7) Å	µ = 2.06 mm⁻¹
c = 12.588 (5) Å	T = 296 K
α = 75.88 (4)°	0.40 × 0.40 × 0.05 mm
β = 100.92 (3)°

Data collection top

Rigaku AFC-7S diffractometer	3290 reflections with F² > 2σ(F²)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.076
T_min = 0.673, T_max = 0.902	3 standard reflections every 150 reflections
6713 measured reflections	intensity decay: 4.8%
6360 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.060	389 parameters
wR(F²) = 0.207	H-atom parameters constrained
S = 1.00	Δρ_max = 1.17 e Å⁻³
6360 reflections	Δρ_min = −1.13 e Å⁻³

Special details top

Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY

Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Co(1)	0.71696 (10)	0.72533 (9)	0.93041 (8)	0.0137 (2)
Co(2)	0.73172 (10)	0.93813 (9)	0.75658 (8)	0.0141 (2)
Co(3)	0.51954 (10)	0.72856 (9)	0.74180 (8)	0.0140 (2)
Ca(1)	0.81420 (15)	0.67221 (15)	0.69882 (13)	0.0190 (3)
O(1)	0.6046 (4)	0.8286 (4)	0.8436 (4)	0.0141 (10)
O(2)	0.8387 (5)	0.8207 (4)	0.8306 (4)	0.0176 (11)
O(3)	0.6625 (5)	0.8240 (4)	0.6610 (4)	0.0154 (10)
O(4)	0.6435 (5)	0.6261 (4)	0.8183 (4)	0.0160 (10)
O(5)	0.8438 (5)	0.6279 (5)	1.0143 (4)	0.0224 (12)
O(6)	1.0147 (6)	0.6325 (6)	1.1499 (5)	0.0377 (16)
O(7)	0.5867 (5)	0.6299 (5)	1.0215 (4)	0.0227 (12)
O(8)	0.4950 (6)	0.6300 (6)	1.1655 (5)	0.0327 (14)
O(9)	0.8615 (5)	1.0388 (5)	0.6638 (4)	0.0256 (12)
O(10)	0.8934 (7)	1.2014 (6)	0.5255 (6)	0.052 (2)
O(11)	0.7888 (5)	1.0409 (4)	0.8634 (4)	0.0176 (11)
O(12)	0.7064 (8)	1.1589 (7)	0.9394 (5)	0.051 (2)
O(13)	0.4431 (5)	0.6281 (5)	0.6339 (4)	0.0228 (12)
O(14)	0.2633 (7)	0.4911 (7)	0.5851 (6)	0.051 (2)
O(15)	0.4032 (5)	0.8393 (5)	0.6783 (4)	0.0203 (11)
O(16)	0.2518 (6)	0.9176 (6)	0.7259 (5)	0.0399 (16)
O(17)	0.9506 (7)	0.8551 (6)	0.6103 (6)	0.050 (2)
O(18)	0.6561 (6)	0.6337 (6)	0.5383 (5)	0.0358 (16)
O(19)	0.7455 (5)	0.4350 (6)	0.7370 (5)	0.0348 (15)
O(20)	0.9788 (6)	0.6105 (6)	0.8499 (5)	0.0313 (14)
O(21)	0.9474 (6)	0.5947 (6)	0.5991 (5)	0.0395 (16)
O(22)	0.0992 (5)	0.9178 (6)	0.8899 (5)	0.0315 (14)
O(23)	0.6372 (6)	0.8910 (6)	0.4401 (5)	0.0411 (17)
O(24)	0.8213 (16)	0.7798 (16)	0.3566 (14)	0.068 (4)	0.54 (3)
N(1)	0.7746 (6)	0.8266 (5)	1.0404 (5)	0.0168 (12)
N(2)	0.6218 (5)	1.0576 (5)	0.6830 (5)	0.0149 (12)
N(3)	0.3720 (6)	0.6372 (5)	0.8218 (5)	0.0167 (12)
C(1)	0.9207 (8)	0.6772 (7)	1.0912 (6)	0.0236 (17)
C(2)	0.5724 (7)	0.6812 (7)	1.0984 (6)	0.0195 (15)
C(3)	0.8963 (8)	0.7956 (8)	1.1112 (7)	0.0279 (18)
C(4)	0.6595 (8)	0.8098 (7)	1.0997 (7)	0.0251 (17)
C(5)	0.8276 (9)	1.1327 (8)	0.5968 (7)	0.0300 (19)
C(6)	0.7038 (9)	1.1044 (7)	0.8667 (6)	0.0253 (17)
C(7)	0.6939 (9)	1.1555 (8)	0.6011 (7)	0.031 (2)
C(8)	0.5893 (8)	1.1025 (7)	0.7744 (6)	0.0213 (16)
C(9)	0.3283 (8)	0.5566 (8)	0.6488 (7)	0.0266 (18)
C(10)	0.3213 (7)	0.8398 (7)	0.7426 (6)	0.0217 (16)
C(11)	0.2752 (8)	0.5578 (7)	0.7508 (7)	0.0246 (17)
C(12)	0.3138 (8)	0.7343 (7)	0.8439 (6)	0.0237 (17)
H(1)	0.7947	0.9079	1.0048	0.020*
H(2)	0.5452	1.0172	0.6476	0.018*
H(3)	0.4015	0.5889	0.8864	0.020*
H(4)	0.8859	0.7841	1.1867	0.033*
H(5)	0.9702	0.8623	1.0944	0.033*
H(6)	0.6091	0.8711	1.0637	0.030*
H(7)	0.6904	0.8183	1.1738	0.030*
H(8)	0.7057	1.2340	0.6207	0.037*
H(9)	0.6423	1.1567	0.5303	0.037*
H(10)	0.5117	1.0479	0.8014	0.026*
H(11)	0.5732	1.1844	0.7478	0.026*
H(12)	0.1962	0.5897	0.7294	0.030*
H(13)	0.2551	0.4749	0.7923	0.030*
H(14)	0.3632	0.7642	0.9071	0.028*
H(15)	0.2237	0.7009	0.8558	0.028*
H(16)	0.9166	0.8498	0.8586	0.021*
H(17)	0.6408	0.8554	0.5940	0.018*
H(18)	0.6107	0.5500	0.8413	0.019*
H(19)	0.9347	0.9179	0.6258	0.060*
H(20)	1.0115	0.8682	0.5710	0.060*
H(21)	0.6803	0.5862	0.5078	0.043*
H(22)	0.5806	0.5997	0.5577	0.043*
H(23)	0.7839	0.4056	0.7991	0.042*
H(24)	0.6626	0.4130	0.7365	0.042*
H(25)	0.9410	0.5690	0.9048	0.038*
H(26)	1.0209	0.5666	0.8310	0.038*
H(27)	0.8977	0.5387	0.5677	0.047*
H(28)	0.9823	0.6540	0.5514	0.047*
H(29)	0.1383	0.8707	0.9402	0.038*
H(30)	0.1340	0.8916	0.8478	0.038*
H(31)	0.6683	0.8379	0.4229	0.049*
H(32)	0.6765	0.9500	0.3952	0.049*
H(33)	0.8162	0.7109	0.3878	0.079*	0.54
H(34)	0.8708	0.8215	0.3978	0.079*	0.54

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co(1)	0.0127 (4)	0.0144 (5)	0.0121 (4)	0.0010 (3)	0.0026 (3)	−0.0006 (3)
Co(2)	0.0116 (4)	0.0139 (5)	0.0152 (4)	0.0011 (3)	0.0034 (3)	−0.0007 (3)
Co(3)	0.0110 (4)	0.0161 (5)	0.0135 (4)	0.0006 (3)	0.0026 (3)	−0.0024 (3)
Ca(1)	0.0147 (7)	0.0214 (8)	0.0208 (7)	0.0042 (6)	0.0039 (6)	−0.0027 (6)
O(1)	0.012 (2)	0.014 (2)	0.018 (2)	0.003 (2)	−0.0010 (19)	−0.008 (2)
O(2)	0.013 (2)	0.016 (2)	0.020 (2)	0.002 (2)	−0.000 (2)	−0.001 (2)
O(3)	0.018 (2)	0.015 (2)	0.013 (2)	0.003 (2)	0.004 (2)	−0.001 (2)
O(4)	0.018 (2)	0.012 (2)	0.018 (2)	0.004 (2)	0.005 (2)	−0.003 (2)
O(5)	0.025 (2)	0.018 (2)	0.023 (2)	0.008 (2)	0.001 (2)	−0.000 (2)
O(6)	0.032 (3)	0.039 (3)	0.038 (3)	0.019 (3)	−0.007 (2)	0.001 (3)
O(7)	0.020 (2)	0.018 (2)	0.024 (2)	−0.004 (2)	0.007 (2)	0.001 (2)
O(8)	0.029 (3)	0.034 (3)	0.032 (3)	−0.003 (2)	0.017 (2)	−0.002 (2)
O(9)	0.020 (2)	0.021 (2)	0.034 (3)	0.001 (2)	0.015 (2)	0.002 (2)
O(10)	0.058 (4)	0.040 (4)	0.057 (4)	0.018 (3)	0.039 (4)	0.025 (3)
O(11)	0.020 (2)	0.017 (2)	0.015 (2)	−0.000 (2)	−0.002 (2)	−0.009 (2)
O(12)	0.067 (5)	0.073 (5)	0.033 (3)	0.046 (4)	−0.014 (3)	−0.033 (3)
O(13)	0.015 (2)	0.031 (3)	0.019 (2)	−0.007 (2)	0.009 (2)	−0.006 (2)
O(14)	0.035 (3)	0.069 (5)	0.052 (4)	−0.022 (3)	0.012 (3)	−0.045 (4)
O(15)	0.016 (2)	0.023 (2)	0.021 (2)	0.007 (2)	0.002 (2)	−0.001 (2)
O(16)	0.034 (3)	0.038 (3)	0.050 (4)	0.019 (3)	0.020 (3)	0.008 (3)
O(17)	0.041 (4)	0.034 (3)	0.083 (5)	0.003 (3)	0.043 (4)	−0.005 (3)
O(18)	0.028 (3)	0.048 (4)	0.045 (3)	0.006 (3)	0.010 (2)	−0.033 (3)
O(19)	0.020 (3)	0.033 (3)	0.047 (3)	0.002 (2)	0.006 (2)	−0.002 (3)
O(20)	0.030 (3)	0.036 (3)	0.030 (3)	0.009 (2)	0.004 (2)	−0.009 (2)
O(21)	0.040 (3)	0.029 (3)	0.051 (4)	−0.003 (2)	0.025 (3)	−0.007 (3)
O(22)	0.020 (2)	0.039 (3)	0.037 (3)	0.002 (2)	0.002 (2)	−0.016 (2)
O(23)	0.039 (3)	0.053 (4)	0.029 (3)	0.020 (3)	0.009 (3)	0.010 (3)
O(24)	0.063 (10)	0.071 (11)	0.066 (10)	0.016 (9)	0.003 (8)	−0.009 (9)
N(1)	0.021 (3)	0.015 (3)	0.015 (3)	0.003 (2)	0.006 (2)	−0.004 (2)
N(2)	0.013 (2)	0.013 (2)	0.017 (3)	−0.001 (2)	0.003 (2)	−0.001 (2)
N(3)	0.015 (3)	0.017 (3)	0.016 (3)	0.004 (2)	−0.000 (2)	−0.001 (2)
C(1)	0.023 (4)	0.018 (4)	0.029 (4)	0.004 (3)	0.010 (3)	0.001 (3)
C(2)	0.015 (3)	0.019 (3)	0.023 (3)	0.003 (2)	0.001 (3)	−0.002 (3)
C(3)	0.026 (4)	0.034 (4)	0.028 (4)	0.008 (3)	0.002 (3)	−0.014 (3)
C(4)	0.024 (4)	0.022 (4)	0.027 (4)	−0.004 (3)	0.009 (3)	−0.006 (3)
C(5)	0.028 (4)	0.025 (4)	0.037 (5)	−0.002 (3)	0.014 (3)	−0.008 (3)
C(6)	0.038 (4)	0.021 (4)	0.023 (4)	0.014 (3)	0.005 (3)	−0.008 (3)
C(7)	0.036 (4)	0.023 (4)	0.034 (4)	0.018 (3)	0.012 (4)	0.013 (3)
C(8)	0.029 (4)	0.025 (4)	0.015 (3)	0.010 (3)	0.005 (3)	−0.007 (3)
C(9)	0.019 (3)	0.029 (4)	0.031 (4)	−0.000 (3)	0.005 (3)	−0.009 (3)
C(10)	0.016 (3)	0.021 (4)	0.025 (4)	0.003 (3)	−0.001 (3)	−0.003 (3)
C(11)	0.019 (3)	0.023 (4)	0.035 (4)	−0.005 (3)	0.009 (3)	−0.016 (3)
C(12)	0.022 (4)	0.022 (4)	0.027 (4)	0.004 (3)	0.011 (3)	0.000 (3)

Geometric parameters (Å, º) top

Co(1)—O(1)	1.877 (5)	N(3)—C(11)	1.491 (10)
Co(1)—O(2)	1.903 (5)	N(3)—C(12)	1.484 (12)
Co(1)—O(4)	1.941 (5)	C(1)—C(3)	1.511 (14)
Co(1)—O(5)	1.932 (5)	C(2)—C(4)	1.511 (10)
Co(1)—O(7)	1.894 (5)	C(5)—C(7)	1.499 (14)
Co(1)—N(1)	1.923 (6)	C(6)—C(8)	1.503 (11)
Co(2)—O(1)	1.888 (4)	C(9)—C(11)	1.498 (14)
Co(2)—O(2)	1.907 (5)	C(10)—C(12)	1.518 (10)
Co(2)—O(3)	1.895 (5)	O(2)—H(16)	0.842
Co(2)—O(9)	1.918 (5)	O(3)—H(17)	0.843
Co(2)—O(11)	1.904 (5)	O(4)—H(18)	0.842
Co(2)—N(2)	1.943 (6)	O(17)—H(19)	0.841
Co(3)—Ca(1)	3.466 (2)	O(17)—H(20)	0.844
Co(3)—O(1)	1.866 (5)	O(18)—H(21)	0.840
Co(3)—O(3)	1.915 (5)	O(18)—H(22)	0.840
Co(3)—O(4)	1.921 (5)	O(19)—H(23)	0.840
Co(3)—O(13)	1.913 (6)	O(19)—H(24)	0.839
Co(3)—O(15)	1.897 (5)	O(20)—H(25)	0.840
Co(3)—N(3)	1.936 (6)	O(20)—H(26)	0.840
Ca(1)—O(2)	2.572 (6)	O(21)—H(27)	0.840
Ca(1)—O(3)	2.527 (6)	O(21)—H(28)	0.840
Ca(1)—O(4)	2.429 (5)	O(22)—H(29)	0.837
Ca(1)—O(17)	2.355 (6)	O(22)—H(30)	0.839
Ca(1)—O(18)	2.411 (6)	O(23)—H(31)	0.837
Ca(1)—O(19)	2.543 (6)	O(23)—H(32)	0.836
Ca(1)—O(20)	2.406 (6)	O(24)—H(33)	0.775
Ca(1)—O(21)	2.471 (8)	O(24)—H(34)	0.809
O(5)—C(1)	1.280 (9)	N(1)—H(1)	0.910
O(6)—C(1)	1.249 (10)	N(2)—H(2)	0.910
O(7)—C(2)	1.292 (11)	N(3)—H(3)	0.910
O(8)—C(2)	1.220 (10)	C(3)—H(4)	0.951
O(9)—C(5)	1.267 (10)	C(3)—H(5)	0.951
O(10)—C(5)	1.227 (11)	C(4)—H(6)	0.951
O(11)—C(6)	1.288 (12)	C(4)—H(7)	0.947
O(12)—C(6)	1.215 (13)	C(7)—H(8)	0.951
O(13)—C(9)	1.287 (9)	C(7)—H(9)	0.950
O(14)—C(9)	1.219 (12)	C(8)—H(10)	0.952
O(15)—C(10)	1.288 (11)	C(8)—H(11)	0.950
O(16)—C(10)	1.234 (12)	C(11)—H(12)	0.951
N(1)—C(3)	1.477 (10)	C(11)—H(13)	0.948
N(1)—C(4)	1.485 (12)	C(12)—H(14)	0.951
N(2)—C(7)	1.475 (10)	C(12)—H(15)	0.951
N(2)—C(8)	1.489 (12)

O(1)—Co(1)—O(2)	83.4 (2)	Co(2)—O(11)—C(6)	113.5 (4)
O(1)—Co(1)—O(4)	82.8 (2)	Co(3)—O(13)—C(9)	115.3 (6)
O(1)—Co(1)—O(5)	175.6 (2)	Co(3)—O(15)—C(10)	113.6 (4)
O(1)—Co(1)—O(7)	93.8 (2)	Co(1)—N(1)—C(3)	110.3 (6)
O(1)—Co(1)—N(1)	93.2 (2)	Co(1)—N(1)—C(4)	107.1 (4)
O(2)—Co(1)—O(4)	85.6 (2)	C(3)—N(1)—C(4)	115.2 (6)
O(2)—Co(1)—O(5)	92.3 (2)	Co(2)—N(2)—C(7)	109.6 (5)
O(2)—Co(1)—O(7)	176.1 (2)	Co(2)—N(2)—C(8)	104.6 (4)
O(2)—Co(1)—N(1)	97.0 (2)	C(7)—N(2)—C(8)	115.1 (6)
O(4)—Co(1)—O(5)	97.9 (2)	Co(3)—N(3)—C(11)	108.5 (5)
O(4)—Co(1)—O(7)	91.4 (2)	Co(3)—N(3)—C(12)	105.2 (4)
O(4)—Co(1)—N(1)	175.0 (2)	C(11)—N(3)—C(12)	111.8 (6)
O(5)—Co(1)—O(7)	90.5 (2)	O(5)—C(1)—O(6)	123.4 (8)
O(5)—Co(1)—N(1)	86.3 (2)	O(5)—C(1)—C(3)	117.9 (7)
O(7)—Co(1)—N(1)	85.8 (2)	O(6)—C(1)—C(3)	118.7 (7)
O(1)—Co(2)—O(2)	82.9 (2)	O(7)—C(2)—O(8)	122.9 (7)
O(1)—Co(2)—O(3)	82.7 (2)	O(7)—C(2)—C(4)	114.9 (6)
O(1)—Co(2)—O(9)	175.7 (2)	O(8)—C(2)—C(4)	122.2 (8)
O(1)—Co(2)—O(11)	91.0 (2)	N(1)—C(3)—C(1)	110.2 (7)
O(1)—Co(2)—N(2)	96.5 (2)	N(1)—C(4)—C(2)	109.2 (7)
O(2)—Co(2)—O(3)	84.0 (2)	O(9)—C(5)—O(10)	124.4 (9)
O(2)—Co(2)—O(9)	94.7 (2)	O(9)—C(5)—C(7)	117.0 (7)
O(2)—Co(2)—O(11)	94.9 (2)	O(10)—C(5)—C(7)	118.4 (8)
O(2)—Co(2)—N(2)	179.2 (2)	O(11)—C(6)—O(12)	125.5 (8)
O(3)—Co(2)—O(9)	93.4 (2)	O(11)—C(6)—C(8)	115.3 (8)
O(3)—Co(2)—O(11)	173.8 (2)	O(12)—C(6)—C(8)	119.1 (9)
O(3)—Co(2)—N(2)	96.4 (2)	N(2)—C(7)—C(5)	111.7 (7)
O(9)—Co(2)—O(11)	92.8 (2)	N(2)—C(8)—C(6)	109.6 (7)
O(9)—Co(2)—N(2)	86.0 (2)	O(13)—C(9)—O(14)	123.7 (9)
O(11)—Co(2)—N(2)	84.6 (2)	O(13)—C(9)—C(11)	116.2 (7)
Ca(1)—Co(3)—O(1)	93.60 (17)	O(14)—C(9)—C(11)	120.2 (7)
Ca(1)—Co(3)—O(3)	45.55 (17)	O(15)—C(10)—O(16)	124.6 (7)
Ca(1)—Co(3)—O(4)	42.59 (16)	O(15)—C(10)—C(12)	114.8 (7)
Ca(1)—Co(3)—O(13)	82.93 (19)	O(16)—C(10)—C(12)	120.6 (8)
Ca(1)—Co(3)—O(15)	139.35 (16)	N(3)—C(11)—C(9)	112.4 (6)
Ca(1)—Co(3)—N(3)	136.5 (2)	N(3)—C(12)—C(10)	107.0 (7)
O(1)—Co(3)—O(3)	82.8 (2)	Co(1)—O(2)—H(16)	117.0
O(1)—Co(3)—O(4)	83.6 (2)	Co(2)—O(2)—H(16)	116.9
O(1)—Co(3)—O(13)	176.3 (2)	Ca(1)—O(2)—H(16)	117.0
O(1)—Co(3)—O(15)	90.4 (2)	Co(2)—O(3)—H(17)	116.3
O(1)—Co(3)—N(3)	96.7 (2)	Co(3)—O(3)—H(17)	116.2
O(3)—Co(3)—O(4)	85.1 (2)	Ca(1)—O(3)—H(17)	116.2
O(3)—Co(3)—O(13)	93.8 (2)	Co(1)—O(4)—H(18)	116.3
O(3)—Co(3)—O(15)	95.2 (2)	Co(3)—O(4)—H(18)	116.3
O(3)—Co(3)—N(3)	177.9 (2)	Ca(1)—O(4)—H(18)	116.4
O(4)—Co(3)—O(13)	94.6 (2)	Ca(1)—O(17)—H(19)	109.5
O(4)—Co(3)—O(15)	174.0 (2)	Ca(1)—O(17)—H(20)	133.3
O(4)—Co(3)—N(3)	96.9 (2)	H(19)—O(17)—H(20)	117.1
O(13)—Co(3)—O(15)	91.3 (2)	Ca(1)—O(18)—H(21)	109.5
O(13)—Co(3)—N(3)	86.8 (2)	Ca(1)—O(18)—H(22)	109.5
O(15)—Co(3)—N(3)	82.8 (2)	H(21)—O(18)—H(22)	109.4
Co(3)—Ca(1)—O(2)	64.34 (12)	Ca(1)—O(19)—H(23)	109.4
Co(3)—Ca(1)—O(3)	32.76 (10)	Ca(1)—O(19)—H(24)	109.4
Co(3)—Ca(1)—O(4)	32.37 (12)	H(23)—O(19)—H(24)	109.6
Co(3)—Ca(1)—O(17)	111.7 (2)	Ca(1)—O(20)—H(25)	109.5
Co(3)—Ca(1)—O(18)	74.12 (19)	Ca(1)—O(20)—H(26)	109.5
Co(3)—Ca(1)—O(19)	97.28 (16)	H(25)—O(20)—H(26)	109.5
Co(3)—Ca(1)—O(20)	121.95 (18)	Ca(1)—O(21)—H(27)	109.4
Co(3)—Ca(1)—O(21)	153.06 (16)	Ca(1)—O(21)—H(28)	109.4
O(2)—Ca(1)—O(3)	59.84 (16)	H(27)—O(21)—H(28)	109.5
O(2)—Ca(1)—O(4)	62.91 (17)	H(29)—O(22)—H(30)	84.2
O(2)—Ca(1)—O(17)	78.2 (2)	H(31)—O(23)—H(32)	93.0
O(2)—Ca(1)—O(18)	132.2 (2)	H(33)—O(24)—H(34)	105.7
O(2)—Ca(1)—O(19)	128.8 (2)	Co(1)—N(1)—H(1)	108.0
O(2)—Ca(1)—O(20)	75.0 (2)	C(3)—N(1)—H(1)	108.1
O(2)—Ca(1)—O(21)	141.50 (19)	C(4)—N(1)—H(1)	107.9
O(3)—Ca(1)—O(4)	63.09 (16)	Co(2)—N(2)—H(2)	109.1
O(3)—Ca(1)—O(17)	79.3 (2)	C(7)—N(2)—H(2)	109.1
O(3)—Ca(1)—O(18)	72.5 (2)	C(8)—N(2)—H(2)	109.2
O(3)—Ca(1)—O(19)	126.86 (18)	Co(3)—N(3)—H(3)	110.4
O(3)—Ca(1)—O(20)	134.5 (2)	C(11)—N(3)—H(3)	110.3
O(3)—Ca(1)—O(21)	139.57 (19)	C(12)—N(3)—H(3)	110.5
O(4)—Ca(1)—O(17)	135.4 (2)	N(1)—C(3)—H(4)	109.3
O(4)—Ca(1)—O(18)	93.7 (2)	N(1)—C(3)—H(5)	109.3
O(4)—Ca(1)—O(19)	76.6 (2)	C(1)—C(3)—H(4)	109.3
O(4)—Ca(1)—O(20)	92.9 (2)	C(1)—C(3)—H(5)	109.3
O(4)—Ca(1)—O(21)	148.6 (2)	H(4)—C(3)—H(5)	109.4
O(17)—Ca(1)—O(18)	97.1 (2)	N(1)—C(4)—H(6)	109.5
O(17)—Ca(1)—O(19)	148.0 (2)	N(1)—C(4)—H(7)	109.7
O(17)—Ca(1)—O(20)	97.6 (2)	C(2)—C(4)—H(6)	109.3
O(17)—Ca(1)—O(21)	76.0 (2)	C(2)—C(4)—H(7)	109.5
O(18)—Ca(1)—O(19)	77.4 (2)	H(6)—C(4)—H(7)	109.6
O(18)—Ca(1)—O(20)	151.5 (2)	N(2)—C(7)—H(8)	108.7
O(18)—Ca(1)—O(21)	79.4 (2)	N(2)—C(7)—H(9)	108.8
O(19)—Ca(1)—O(20)	77.2 (2)	C(5)—C(7)—H(8)	109.0
O(19)—Ca(1)—O(21)	72.0 (2)	C(5)—C(7)—H(9)	109.1
O(20)—Ca(1)—O(21)	80.6 (2)	H(8)—C(7)—H(9)	109.4
Co(1)—O(1)—Co(2)	97.1 (2)	N(2)—C(8)—H(10)	109.5
Co(1)—O(1)—Co(3)	98.6 (2)	N(2)—C(8)—H(11)	109.6
Co(2)—O(1)—Co(3)	97.7 (2)	C(6)—C(8)—H(10)	109.4
Co(1)—O(2)—Co(2)	95.6 (2)	C(6)—C(8)—H(11)	109.5
Co(1)—O(2)—Ca(1)	101.5 (2)	H(10)—C(8)—H(11)	109.3
Co(2)—O(2)—Ca(1)	105.8 (2)	N(3)—C(11)—H(12)	108.6
Co(2)—O(3)—Co(3)	95.8 (2)	N(3)—C(11)—H(13)	108.8
Co(2)—O(3)—Ca(1)	107.9 (2)	C(9)—C(11)—H(12)	108.7
Co(3)—O(3)—Ca(1)	101.7 (2)	C(9)—C(11)—H(13)	108.8
Co(1)—O(4)—Co(3)	94.5 (2)	H(12)—C(11)—H(13)	109.6
Co(1)—O(4)—Ca(1)	105.5 (2)	N(3)—C(12)—H(14)	110.2
Co(3)—O(4)—Ca(1)	105.0 (2)	N(3)—C(12)—H(15)	110.3
Co(1)—O(5)—C(1)	113.7 (5)	C(10)—C(12)—H(14)	110.0
Co(1)—O(7)—C(2)	115.1 (4)	C(10)—C(12)—H(15)	110.0
Co(2)—O(9)—C(5)	115.6 (6)	H(14)—C(12)—H(15)	109.4

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O(2)—H(16)···O(22)ⁱ	0.84	1.88	2.707 (7)	168
O(3)—H(17)···O(23)	0.84	1.88	2.677 (7)	159
O(4)—H(18)···O(8)ⁱⁱ	0.84	2.07	2.870 (7)	158
O(17)—H(19)···O(9)	0.84	1.92	2.744 (11)	168
O(17)—H(20)···O(10)ⁱⁱⁱ	0.84	2.10	2.850 (13)	148
O(18)—H(21)···O(14)^iv	0.84	1.87	2.699 (12)	168
O(18)—H(22)···O(13)	0.84	2.00	2.708 (9)	141
O(19)—H(23)···O(6)^v	0.84	2.21	2.829 (9)	131
O(19)—H(24)···O(8)ⁱⁱ	0.84	2.14	2.863 (9)	145
O(20)—H(25)···O(5)	0.84	2.17	2.787 (9)	130
O(20)—H(26)···O(6)^v	0.84	2.15	2.765 (10)	130
O(21)—H(27)···O(14)^iv	0.84	2.34	3.043 (9)	142
O(21)—H(28)···O(10)ⁱⁱⁱ	0.84	1.99	2.801 (9)	164
O(22)—H(29)···O(12)^vi	0.84	2.04	2.800 (9)	152
O(22)—H(30)···O(16)	0.84	2.07	2.840 (10)	153
O(23)—H(31)···O(18)	0.84	2.40	2.909 (10)	120
O(23)—H(31)···O(24)	0.84	2.24	3.01 (2)	153
O(23)—H(32)···O(16)^vii	0.84	1.97	2.802 (8)	172
O(24)—H(33)···O(14)^iv	0.78	2.19	2.912 (18)	156
O(24)—H(34)···O(10)ⁱⁱⁱ	0.81	2.53	3.054 (18)	124
N(1)—H(1)···O(11)	0.91	2.03	2.857 (7)	150
N(1)—H(1)···O(22)^vi	0.91	2.55	3.121 (9)	122
N(2)—H(2)···O(15)	0.91	2.18	2.917 (7)	138
N(2)—H(2)···O(23)^vii	0.91	2.36	2.977 (9)	125
N(3)—H(3)···O(7)	0.91	2.36	3.038 (7)	132
N(3)—H(3)···O(7)ⁱⁱ	0.91	2.49	3.259 (8)	143

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

Experimental details

Crystal data
Chemical formula	[CaCo₃(C₄H₅NO₄)₃(OH)₃O(H₂O)₅]·2.54H₂O
M_r	812.92
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	10.474 (3), 11.303 (7), 12.588 (5)
α, β, γ (°)	75.88 (4), 100.92 (3), 104.58 (3)
V (Å³)	1385.6 (10)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.06
Crystal size (mm)	0.40 × 0.40 × 0.05

Data collection
Diffractometer	Rigaku AFC-7S diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.673, 0.902
No. of measured, independent and observed [F² > 2σ(F²)] reflections	6713, 6360, 3290
R_int	0.076
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.060, 0.207, 1.00
No. of reflections	6360
No. of parameters	389
No. of restraints	?
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.17, −1.13

Computer programs: WinAFC (Rigaku/MSC, 2000), CrystalStructure (Rigaku/MSC, 2007), DIRDIF99 (Beurskens et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997).

Selected geometric parameters (Å, º) top

Co(1)—O(1)	1.877 (5)	Ca(1)—O(2)	2.572 (6)
Co(1)—O(2)	1.903 (5)	Ca(1)—O(3)	2.527 (6)
Co(1)—O(4)	1.941 (5)	Ca(1)—O(4)	2.429 (5)
Co(2)—O(1)	1.888 (4)	Ca(1)—O(17)	2.355 (6)
Co(2)—O(2)	1.907 (5)	Ca(1)—O(18)	2.411 (6)
Co(2)—O(3)	1.895 (5)	Ca(1)—O(19)	2.543 (6)
Co(3)—O(1)	1.866 (5)	Ca(1)—O(20)	2.406 (6)
Co(3)—O(3)	1.915 (5)	Ca(1)—O(21)	2.471 (8)
Co(3)—O(4)	1.921 (5)

O(1)—Co(1)—O(2)	83.4 (2)	Co(1)—O(1)—Co(2)	97.1 (2)
O(1)—Co(1)—O(4)	82.8 (2)	Co(1)—O(1)—Co(3)	98.6 (2)
O(2)—Co(1)—O(4)	85.6 (2)	Co(2)—O(1)—Co(3)	97.7 (2)
O(1)—Co(2)—O(2)	82.9 (2)	Co(1)—O(2)—Co(2)	95.6 (2)
O(1)—Co(2)—O(3)	82.7 (2)	Co(1)—O(2)—Ca(1)	101.5 (2)
O(2)—Co(2)—O(3)	84.0 (2)	Co(2)—O(2)—Ca(1)	105.8 (2)
O(1)—Co(3)—O(3)	82.8 (2)	Co(2)—O(3)—Co(3)	95.8 (2)
O(1)—Co(3)—O(4)	83.6 (2)	Co(2)—O(3)—Ca(1)	107.9 (2)
O(3)—Co(3)—O(4)	85.1 (2)	Co(3)—O(3)—Ca(1)	101.7 (2)
O(2)—Ca(1)—O(3)	59.84 (16)	Co(1)—O(4)—Co(3)	94.5 (2)
O(2)—Ca(1)—O(4)	62.91 (17)	Co(1)—O(4)—Ca(1)	105.5 (2)
O(3)—Ca(1)—O(4)	63.09 (16)	Co(3)—O(4)—Ca(1)	105.0 (2)

Acknowledgements

The authors are grateful to Kochi University for financial support.

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