Crystal structure of catena-poly[bis­(tetra­ethyl­ammonium) [tetra­aqua­tris(μ-dicyanamido-κ2N1:N5)bis(dicyanamido-κN1)di­cobaltate(II)] dicyanamide]

Liu, C.; Thuijs, A.E.; Abboud, K.A.

doi:10.1107/S2056989016016637

research communications

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 72| Part 11| November 2016| Pages 1603-1606

https://doi.org/10.1107/S2056989016016637

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Crystal structure of catena-poly[bis(tetraethylammonium) [tetraaquatris(μ-dicyanamido-κ²N¹:N⁵)bis(dicyanamido-κN¹)dicobaltate(II)] dicyanamide]

Chen Liu,^a ^* Annaliese E. Thuijs ^b and Khalil A. Abboud ^b

^aDepartment of Chemistry and Environmental Science, Grenfell Campus, Memorial University of Newfoundland, Corner Brook, NL, A2H 5G4, Canada, and ^bDepartment of Chemistry, University of Florida, Gainesville, FL, 32611-7200, USA
^*Correspondence e-mail: cliu@grenfell.mun.ca

Edited by M. Weil, Vienna University of Technology, Austria (Received 30 September 2016; accepted 17 October 2016; online 21 October 2016)

The structure of the title compound, [N(C₂H₅)₄]₂[Co₂(C₂N₃)₅(H₂O)₄](C₂N₃), is a new example of a metal–dicyanamide coordination polymer which exhibits a unique three-dimensional framework of covalently linked Co^II chains. All bridging dicyanamide ligands in the title structure are in the μ_1,5-bridging mode. The anionic Co^II-dicyanamide network is templated by tetraethylammonium cations residing in a series of channels extending along the b axis where additional non-coordinating dicyanamidate anions are also located. The framework structure is further stabilized by O—H⋯N hydrogen bonding between aqua ligands and dicyanamido ligands or the dicyanamide anion. In addition, C—H⋯N interactions are present between the tetraethylammonium cations and dicyanamide amide nitrogen atoms.

Keywords: crystal structure; metal dicyanamide coordination polymer; cation template; tetraethylammonium; O—H⋯N hydrogen bonding; crystal structure.

CCDC reference: 1510337

1. Chemical context

Dicyanamide is a versatile ligand in the design and synthesis of coordination polymers due to its ability to coordinate to transition metal ions in a number of different modes involving some or all of its three nitrogen atoms (Batten & Murray, 2003 ). Reactions between transition metal ions and dicyanamide have mainly produced three types of coordination polymers, including the neutral binary systems of M^II(dca)₂ (dca = dicyanamide), complexes derived from M^II(dca)₂ by including a co-ligand, and cation-templated anionic [M^II(dca)_n]^(2–n) (n = 3,4) networks (Batten & Murray, 2003). These metal–dicyanamide coordination polymers exhibit a wide range of structures, from three-dimensional rutile-like structures for M^II(dca)₂ to networks of reduced dimensions when a co-ligand or a counter-cation is included. Much of the interest in metal–dicyanamide coordination polymers has been focused on their structural diversities and their magnetic properties, particularly the long-range ferromagnetic ordering observed in some of the M^II(dca)₂ networks (Kurmoo & Kepert, 1998 ). Compared to co-ligand-modified derivatives of M^II(dca)₂ complexes, there are fewer examples of cation-templated anionic [M^II(dca)_n]^(2–n) (n = 3,4) networks. We recently prepared the title compound, (N(C₂H₅)₄)₂[Co₂(H₂O)₄(C₂N₃)₅](C₂N₃), as a new example of a cation-templated metal–dicyanamide coordination polymer. The title structure presents a unique single three-dimensional network of covalently linked chains rather than a two-dimensional structure as commonly observed in many other metal–dicyanamide coordination polymers.

2. Structural commentary

In the asymmetric unit of the title coordination polymer, there are two Co^II ions, Co1 and Co2, linked by a μ_1,5-bridging dicyanamide ligand (Fig. 1). Co2 is coordinated by three dicyanamide ligands via their terminal nitrogen atoms and two trans-positioned aqua ligands, forming an N₄O₂ octahedral coordination sphere that is slightly elongated along the two Co—O bonds. Co1 is coordinated by one dicyanamide ligand via its terminal nitrogen atom and two trans-positioned aqua ligands. The likewise distorted octahedral N₄O₂ coordination sphere around Co1 is completed by additional bonds to N20ⁱⁱ and N15^xi [symmetry codes: (ii) x, 2 − y, − $[{1\over 2}]$ + z; (xi) − $[{1\over 2}]$ + x, $[{2\over 3}]$ − y, − $[{1\over 2}]$ + z] of two symmetry-generated dicyanamide ligands. The asymmetric unit also contains two tetraethylammonium counter-ions and a non-coordinating dicyanamide anion. Two nitrogen atoms, N3/N3′ of one terminal ligand and N55/N56 of the anion, are disordered and were refined over two sets of sites.

Figure 1
A view of the asymmetric unit of the title compound, showing the atom labeling. Displacement ellipsoids are drawn at 50% probability level. All disordered components are shown.

In the crystal, a μ_1,5-dca-bridged corrugated Co^II chain can be seen parallel to the [101] direction and is composed of Co^II ions generated by a c glide plane parallel to the ac plane. Among the four dca ligands on each Co^II cation, three are in μ_1,5-bridging mode with two bridging within the same chain and one bridging to another chain. The remaining fourth dca ligand [N1,C2,N3(N3′),C4,N5 for Co1 and N21,C22,N23,C24,N25 for Co2] is mono-dentate non-bridging. In the chain, the distances between two neighboring Co^II atoms linked by μ_1,5-dca ligands alternate between 8.1484 (8) Å (Co1⋯Co2) and 8.5620 (8) Å [Co2⋯Co1^ix, symmetry code: (ix) $[{1\over 2}]$ + x, $[{2\over 3}]$ − y, $[{1\over 2}]$ + z]. All of the inter-chain Co⋯Co distances across μ_1,5-dca bridges are of the same length, viz. 8.5517 (8) Å. These distances are similar to other single μ_1,5-dca bridges reported in the literature (van der Werff et al., 2001 ; Schlueter et al., 2005 ; Biswas et al., 2006 ). In the title structure, each chain is linked to four other chains generated by a c glide plane via the inter-chain μ_1,5-dca ligands at each Co^II site [Co1⋯Co2ⁱⁱ, Co2⋯Co1^xii; symmetry code: (xii) x, 2 − y, $[{1\over 2}]$ + z; Co1^ix⋯Co2^v; symmetry code: (ix) $[{1\over 2}]$ + x, $[{2\over 3}]$ − y, $[{1\over 2}]$ + z, and Co2^ix⋯Co1^x; symmetry code: (x) $[{1\over 2}]$ + x, − $[{1\over 2}]$ + y, 1 + z], resulting in a single three-dimensional network of covalently linked parallel chains. This is in contrast to the layered structures observed in a number of [M^II(dca)_n]⁽²⁻ⁿ⁾ (n = 3, 4) networks that exhibit parallel sheets linked in the third dimension via μ_1,5-dca ligands (Batten & Murray, 2003; Schlueter et al., 2005; Biswas et al., 2006). As a result of the mono-dentate non-bridging dca ligands in the title compound, the commonly observed (4,4) nets in other metal–dca networks are absent in its structure. However, channels extending along the b axis can still be seen in the title structure and these are occupied by columns of tetraethylammonium cations (Fig. 2) and dca⁻ anions. Similar to other cation-templated anionic [M^II(dca)_n]⁽²⁻ⁿ⁾ (n = 3, 4) networks, interpenetration is not observed in the title structure due to the presence of tetraethylammonium cations in the void space, making these structures potential candidates for investigating their ability of storing guest molecules.

Figure 2
Crystal packing of the title compound, showing hydrogen bonds as dashed lines.

3. Supramolecular features

Hydrogen bonding is generally not observed amongst the neutral M^II(dca)₂ networks. Upon introducing co-ligands or counter-ions, the derived M^II(dca)₂L_n (L: co-ligand) and cation-templated [M^II(dca)_n]^(2–n) (n = 3,4) complexes display hydrogen bonding. In most of the M^II(dca)₂ derivatives, the hydrogen bonds are of non-classical C—H⋯X (X = N, O) types (Tong et al., 2003 ; Biswas et al., 2006; Rajan et al., 2013 ). In the title structure, hydrogen bonds are mainly of the classical O—H⋯N type between OH groups of coordinating water molecules and nitrogen atoms of the non-coordinating dca⁻ anion or the mono-dentate non-bridging dca ligands. Some hydrogen bonds in the title structure are bifurcated between two donor water molecules located on two neighboring chains stacked along the b axis and thus hold these chains in place along the b axis. Chains related by c glide-plane symmetry are primarily linked via single μ_1,5-dca ligands as described in the previous section, but are further stabilized by hydrogen bonds across the non-coordinating dca⁻ anions (N51 and N55/56) and by hydrogen bonds involving N1 and N25 of the mono-dentate non-bridging dca ligand. In addition to the O—H⋯N hydrogen bonds, C—H⋯N hydrogen bonds are also present in the title structure between C—H groups of the tetraethylammonium cations and dicyanamide amide nitrogen atoms (Fig. 2). The hydrogen-bond lengths and angles are summarized in Table 1.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N25ⁱ	0.79 (5)	2.08 (5)	2.862 (4)	168 (4)
O1—H1B⋯N55ⁱⁱ	0.71 (4)	2.09 (4)	2.792 (7)	168 (4)
O1—H1B⋯N56ⁱⁱ	0.71 (4)	2.22 (4)	2.922 (9)	170 (4)
O2—H2A⋯N25ⁱⁱⁱ	0.84 (4)	2.03 (4)	2.862 (4)	172 (3)
O2—H2B⋯N55^iv	0.71 (4)	2.27 (4)	2.963 (8)	169 (4)
O2—H2B⋯N56^iv	0.71 (4)	2.12 (4)	2.819 (8)	171 (4)
O3—H3A⋯N51	0.77 (4)	2.07 (4)	2.822 (4)	165 (4)
O3—H3B⋯N1^v	0.84 (6)	2.09 (6)	2.904 (4)	162 (5)
O4—H4A⋯N51^vi	0.74 (4)	2.23 (4)	2.958 (4)	172 (4)
O4—H4B⋯N1^vii	0.77 (5)	2.07 (5)	2.833 (4)	169 (5)
C105—H10L⋯N18ⁱ	0.99	2.57	3.439 (5)	146
C202—H20E⋯N8^viii	0.98	2.60	3.579 (5)	173
C204—H20H⋯N53^vi	0.98	2.49	3.316 (4)	142
Symmetry codes: (i) $[x-{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (ii) $[x, -y+2, z-{\script{1\over 2}}]$ ; (iii) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (iv) $[x, -y+1, z-{\script{1\over 2}}]$ ; (v) $[x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (vi) x, y+1, z; (vii) $[x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (viii) x, y-1, z.

4. Synthesis and crystallization

The title compound was prepared in a reaction where Co(NO₃)₂·6H₂O (1 mmol, 291 mg), NaN(CN)₂ (1.5 mmol, 133.55 mg), and (C₂H₅)₄NCl (1.5 mmol, 249 mg) were dissolved in 40 ml of deionized water to produce a dark-red solution. Upon standing for one month, irregularly shaped red crystals (95 mg, yield 22.4%) suitable for X-ray diffraction were collected by vacuum filtration and washed with deionized water. Selected IR bands (KBr, cm⁻¹): 3370 (O—H), 2977 (C—H), 2300, 2273, 2255, 2236, 2182, 2141 (C≡N), 1365 (C—N amide), 1172 (C—N amine). Elemental analysis calculated for C₂₈H₄₈Co₂N₂₀O₄: C 39.72, H 5.71, N 33.08%. Found: C 39.81, H 5.37, N 32.74%.

5. Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 2. C-bound H atoms were positioned geometrically (C—H = 0.98/0.99 Å) and allowed to ride with U_iso(H) = 1.2/1.5U_eq(C) whereby methyl H atoms were allowed to rotate around the corresponding C—C bond. Two nitrogen atoms, N3/N3′ and N55/N56, were disordered and refined in two parts each with their respective site-occupation factors refined dependently [occupation ratios of 0.33 (4):0.67 (4) and 0.48 (3):0.52 (3), respectively] and with independent U_eq parameters for each of the N atoms. All of the water H atoms were obtained from a difference Fourier map and refined freely.

Table 2
Experimental details

Crystal data
Chemical formula	(C₈H₂₀N)₂[Co₂(C₂N₃)₅(H₂O)₄](C₂N₃)
M_r	846.72
Crystal system, space group	Monoclinic, Cc
Temperature (K)	100
a, b, c (Å)	23.9836 (19), 7.3271 (6), 22.6809 (17)
β (°)	94.4257 (14)
V (Å³)	3973.8 (5)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.90
Crystal size (mm)	0.16 × 0.16 × 0.10

Data collection
Diffractometer	Bruker APEXII DUO CCD
Absorption correction	Analytical based on measured indexed crystal faces (SHELXTL2014; Sheldrick, 2015a )
T_min, T_max	0.898, 0.947
No. of measured, independent and observed [I > 2σ(I)] reflections	26031, 9018, 8397
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.070, 1.02
No. of reflections	9018
No. of parameters	519
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	1.10, −0.22
Absolute structure	Flack x determined using 3859 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.016 (4)
Computer programs: APEX2 and SAINT (Bruker, 2008 ), SHELXT2014 (Sheldrick, 2015a), SHELXL2014 (Sheldrick, 2015b ), XP in SHELXTL-Plus (Sheldrick, 2008 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1510337

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989016016637/wm5330sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989016016637/wm5330Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

catena-Poly[bis(tetraethylammonium) [tetraaquatris(µ-dicyanamido-κ²N¹:N⁵)bis(dicyanamido-κN¹)dicobaltate(II)] dicyanamide] top

Crystal data top

(C₈H₂₀N)₂[Co₂(C₂N₃)₅(H₂O)₄](C₂N₃)	F(000) = 1768
M_r = 846.72	D_x = 1.415 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
a = 23.9836 (19) Å	Cell parameters from 9967 reflections
b = 7.3271 (6) Å	θ = 2.0–28.0°
c = 22.6809 (17) Å	µ = 0.90 mm⁻¹
β = 94.4257 (14)°	T = 100 K
V = 3973.8 (5) Å³	Irregular, red
Z = 4	0.16 × 0.16 × 0.10 mm

Data collection top

Bruker APEXII DUO CCD diffractometer	8397 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.026
phi and ω scans	θ_max = 27.5°, θ_min = 1.7°
Absorption correction: analytical based on measured indexed crystal faces (SHELXTL2014; Sheldrick, 2015a)	h = −30→30
T_min = 0.898, T_max = 0.947	k = −9→9
26031 measured reflections	l = −27→29
9018 independent reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.028	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.070	w = 1/[σ²(F_o²) + (0.0456P)²] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max = 0.001
9018 reflections	Δρ_max = 1.10 e Å⁻³
519 parameters	Δρ_min = −0.22 e Å⁻³
2 restraints	Absolute structure: Flack x determined using 3859 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.016 (4)

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. All H atoms were positioned geometrically ( C—H = 0.93/1.00 Å) and allowed to ride with U_iso(H)= 1.2/1.5U_eq(C). Methyl ones were allowed to rotate around the corresponding C—C.

The asymmetric unit consists of a 2 Co units with each coordinated to four diamine ligand forming a square plane and two water ligands trans to each other.. The asymmetric unit also contains two tetraethylammonium counterions. Two nitrogen atoms, N3/N3' and N55/N56, were disordered and refined in two parts each with their site occupation factors dependently refined. All of the water protons were obtained from a Difference Fourier map and refined freely.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Co1	0.45296 (2)	1.02347 (5)	0.23954 (2)	0.01173 (10)
Co2	0.70898 (2)	0.98381 (6)	0.49718 (2)	0.01198 (10)
O1	0.42840 (11)	1.2865 (3)	0.21237 (11)	0.0182 (5)
H1A	0.4119 (19)	1.345 (6)	0.235 (2)	0.038 (12)*
H1B	0.4509 (17)	1.337 (6)	0.2020 (16)	0.020 (11)*
O2	0.47620 (10)	0.7567 (3)	0.26745 (11)	0.0184 (5)
H2A	0.4479 (15)	0.700 (5)	0.2772 (14)	0.014 (8)*
H2B	0.4867 (16)	0.707 (6)	0.2440 (18)	0.020 (11)*
O3	0.68557 (10)	0.7243 (3)	0.46262 (10)	0.0172 (4)
H3A	0.6660 (17)	0.671 (5)	0.4820 (18)	0.022 (10)*
H3B	0.717 (2)	0.673 (8)	0.462 (2)	0.066 (16)*
O4	0.73049 (10)	1.2503 (3)	0.52824 (10)	0.0165 (4)
H4A	0.7045 (17)	1.301 (6)	0.5321 (17)	0.024 (11)*
H4B	0.748 (2)	1.305 (7)	0.507 (2)	0.041 (13)*
N1	0.27918 (17)	0.9826 (4)	0.44658 (17)	0.0263 (8)
N3	0.3496 (7)	1.110 (2)	0.3882 (6)	0.014 (3)*	0.33 (4)
N3'	0.3369 (4)	1.1453 (11)	0.3777 (3)	0.0170 (17)*	0.67 (4)
N5	0.38584 (12)	1.0199 (4)	0.29474 (13)	0.0172 (6)
N6	0.50206 (11)	1.1338 (3)	0.31233 (11)	0.0186 (5)
N8	0.55339 (11)	1.2440 (4)	0.40377 (11)	0.0198 (6)
N10	0.63870 (10)	1.1001 (3)	0.45012 (11)	0.0176 (5)
N11	0.77978 (10)	0.8675 (3)	0.54269 (11)	0.0185 (5)
N13	0.87084 (11)	0.7274 (4)	0.57243 (12)	0.0275 (7)
N15	0.90600 (10)	0.5935 (3)	0.66723 (11)	0.0179 (5)
N16	0.66067 (11)	0.9433 (4)	0.56980 (12)	0.0165 (5)
N18	0.61244 (11)	0.8416 (4)	0.65572 (12)	0.0208 (6)
N20	0.52420 (11)	0.9548 (4)	0.69062 (12)	0.0171 (5)
N21	0.75691 (12)	1.0268 (4)	0.42431 (13)	0.0172 (6)
N23	0.79811 (11)	1.1485 (4)	0.33595 (11)	0.0219 (6)
N25	0.88281 (14)	1.0353 (4)	0.29320 (16)	0.0243 (8)
C2	0.30902 (13)	1.0444 (4)	0.41469 (13)	0.0167 (6)
C4	0.36385 (12)	1.0633 (4)	0.33577 (13)	0.0158 (6)
C7	0.52810 (12)	1.1808 (4)	0.35482 (13)	0.0144 (6)
C9	0.59893 (12)	1.1634 (4)	0.42615 (12)	0.0143 (6)
C12	0.82135 (13)	0.7985 (4)	0.55973 (13)	0.0171 (6)
C14	0.88662 (12)	0.6596 (4)	0.62471 (13)	0.0175 (6)
C17	0.63568 (12)	0.9025 (4)	0.60908 (13)	0.0138 (6)
C19	0.56523 (12)	0.9077 (4)	0.67179 (13)	0.0151 (6)
C22	0.77826 (12)	1.0776 (4)	0.38380 (13)	0.0151 (6)
C24	0.84342 (13)	1.0826 (4)	0.31572 (13)	0.0175 (6)
N51	0.63136 (15)	0.4857 (4)	0.53742 (16)	0.0268 (8)
C52	0.60294 (12)	0.4231 (4)	0.57142 (14)	0.0159 (6)
N53	0.57322 (12)	0.3337 (4)	0.60740 (13)	0.0256 (7)
C54	0.54159 (14)	0.4164 (4)	0.64236 (16)	0.0223 (7)
N55	0.5044 (5)	0.4734 (8)	0.6665 (5)	0.019 (2)*	0.48 (3)
N56	0.5199 (5)	0.4749 (9)	0.6832 (5)	0.021 (2)*	0.52 (3)
N100	0.20492 (11)	0.8554 (3)	0.74448 (12)	0.0167 (5)
C101	0.21237 (15)	0.9688 (5)	0.80049 (17)	0.0272 (7)
H10A	0.2457	1.0473	0.7982	0.033*
H10B	0.2198	0.8854	0.8345	0.033*
C102	0.16270 (18)	1.0892 (6)	0.8122 (2)	0.0451 (10)
H10C	0.1710	1.1572	0.8491	0.068*
H10D	0.1555	1.1751	0.7794	0.068*
H10E	0.1296	1.0128	0.8158	0.068*
C103	0.15273 (13)	0.7392 (5)	0.74406 (14)	0.0231 (7)
H10F	0.1494	0.6673	0.7070	0.028*
H10G	0.1199	0.8210	0.7436	0.028*
C104	0.15073 (16)	0.6084 (5)	0.79603 (16)	0.0321 (8)
H10H	0.1157	0.5392	0.7921	0.048*
H10I	0.1824	0.5239	0.7964	0.048*
H10J	0.1528	0.6779	0.8330	0.048*
C105	0.19842 (15)	0.9746 (5)	0.68951 (17)	0.0283 (8)
H10K	0.1927	0.8945	0.6544	0.034*
H10L	0.1644	1.0500	0.6914	0.034*
C106	0.24752 (17)	1.0999 (6)	0.6811 (2)	0.0452 (11)
H10M	0.2399	1.1714	0.6449	0.068*
H10N	0.2530	1.1825	0.7151	0.068*
H10O	0.2814	1.0267	0.6780	0.068*
C107	0.25726 (14)	0.7379 (4)	0.74309 (15)	0.0228 (7)
H10P	0.2903	0.8193	0.7452	0.027*
H10Q	0.2603	0.6602	0.7789	0.027*
C108	0.25941 (16)	0.6164 (6)	0.68945 (17)	0.0352 (9)
H10R	0.2944	0.5465	0.6925	0.053*
H10S	0.2276	0.5321	0.6875	0.053*
H10T	0.2577	0.6917	0.6536	0.053*
N200	0.46116 (10)	0.7171 (3)	0.48654 (11)	0.0159 (5)
C201	0.47345 (14)	0.7741 (5)	0.42451 (14)	0.0251 (7)
H20A	0.4679	0.9076	0.4206	0.030*
H20B	0.4461	0.7140	0.3958	0.030*
C202	0.53259 (15)	0.7274 (5)	0.40827 (15)	0.0274 (7)
H20C	0.5373	0.7682	0.3678	0.041*
H20D	0.5600	0.7890	0.4357	0.041*
H20E	0.5383	0.5951	0.4109	0.041*
C203	0.50310 (13)	0.7976 (4)	0.53272 (15)	0.0226 (7)
H20F	0.5410	0.7536	0.5253	0.027*
H20G	0.4945	0.7531	0.5722	0.027*
C204	0.50327 (14)	1.0055 (4)	0.53314 (15)	0.0235 (7)
H20H	0.5311	1.0493	0.5638	0.035*
H20I	0.5126	1.0507	0.4945	0.035*
H20J	0.4662	1.0502	0.5414	0.035*
C205	0.40225 (13)	0.7789 (5)	0.49619 (16)	0.0274 (7)
H20K	0.3762	0.7217	0.4656	0.033*
H20L	0.4000	0.9127	0.4904	0.033*
C206	0.38269 (14)	0.7340 (5)	0.55649 (15)	0.0269 (7)
H20M	0.3444	0.7787	0.5588	0.040*
H20N	0.3836	0.6015	0.5624	0.040*
H20O	0.4075	0.7929	0.5872	0.040*
C207	0.46624 (15)	0.5084 (4)	0.49254 (15)	0.0232 (7)
H20P	0.5051	0.4724	0.4861	0.028*
H20Q	0.4591	0.4736	0.5335	0.028*
C208	0.42651 (15)	0.4023 (5)	0.44990 (16)	0.0281 (7)
H20R	0.4322	0.2712	0.4564	0.042*
H20S	0.3878	0.4343	0.4566	0.042*
H20T	0.4338	0.4331	0.4092	0.042*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0100 (2)	0.0133 (2)	0.0120 (2)	−0.00160 (18)	0.00139 (15)	−0.00165 (18)
Co2	0.0105 (2)	0.0140 (2)	0.0115 (2)	0.00317 (17)	0.00170 (15)	0.00155 (17)
O1	0.0210 (12)	0.0161 (11)	0.0181 (12)	0.0003 (9)	0.0053 (10)	0.0000 (9)
O2	0.0159 (11)	0.0179 (11)	0.0220 (13)	−0.0016 (9)	0.0047 (9)	−0.0020 (10)
O3	0.0160 (11)	0.0181 (11)	0.0179 (11)	0.0010 (9)	0.0040 (9)	0.0015 (9)
O4	0.0160 (11)	0.0166 (11)	0.0172 (11)	0.0028 (9)	0.0040 (9)	0.0019 (9)
N1	0.036 (2)	0.0171 (15)	0.0280 (18)	0.0040 (12)	0.0163 (15)	−0.0004 (12)
N5	0.0148 (13)	0.0189 (13)	0.0182 (15)	0.0002 (10)	0.0040 (11)	0.0019 (10)
N6	0.0166 (12)	0.0209 (13)	0.0181 (13)	0.0018 (10)	0.0000 (10)	−0.0024 (10)
N8	0.0200 (13)	0.0219 (13)	0.0165 (13)	0.0101 (10)	−0.0055 (10)	−0.0058 (10)
N10	0.0167 (12)	0.0200 (13)	0.0156 (13)	0.0033 (10)	−0.0011 (10)	−0.0006 (10)
N11	0.0150 (12)	0.0217 (13)	0.0187 (13)	0.0045 (10)	0.0002 (10)	0.0035 (10)
N13	0.0185 (13)	0.0472 (18)	0.0166 (13)	0.0160 (12)	0.0014 (10)	0.0109 (13)
N15	0.0158 (12)	0.0201 (12)	0.0176 (13)	0.0034 (10)	−0.0003 (10)	0.0025 (10)
N16	0.0149 (12)	0.0180 (13)	0.0168 (13)	0.0032 (10)	0.0026 (10)	0.0012 (10)
N18	0.0173 (13)	0.0262 (14)	0.0199 (13)	0.0081 (10)	0.0088 (10)	0.0083 (11)
N20	0.0164 (13)	0.0173 (13)	0.0182 (14)	0.0015 (10)	0.0047 (10)	0.0020 (10)
N21	0.0166 (14)	0.0193 (13)	0.0161 (14)	0.0031 (11)	0.0041 (11)	0.0010 (11)
N23	0.0245 (14)	0.0232 (13)	0.0196 (13)	0.0058 (11)	0.0118 (11)	0.0056 (11)
N25	0.0240 (18)	0.0209 (15)	0.0301 (19)	−0.0002 (12)	0.0163 (14)	0.0009 (13)
C2	0.0163 (14)	0.0173 (15)	0.0164 (15)	0.0016 (11)	0.0006 (12)	−0.0048 (12)
C4	0.0113 (13)	0.0183 (15)	0.0177 (16)	−0.0053 (11)	−0.0009 (12)	0.0007 (11)
C7	0.0128 (13)	0.0138 (13)	0.0170 (15)	0.0038 (10)	0.0044 (11)	0.0009 (11)
C9	0.0170 (14)	0.0146 (13)	0.0116 (13)	−0.0007 (11)	0.0026 (11)	−0.0033 (10)
C12	0.0188 (14)	0.0199 (14)	0.0129 (14)	0.0018 (12)	0.0029 (11)	0.0019 (11)
C14	0.0118 (13)	0.0198 (14)	0.0209 (16)	0.0037 (11)	0.0020 (11)	−0.0002 (12)
C17	0.0122 (13)	0.0129 (13)	0.0161 (14)	0.0035 (11)	−0.0012 (11)	−0.0015 (11)
C19	0.0181 (14)	0.0135 (13)	0.0136 (14)	−0.0020 (11)	0.0009 (11)	0.0019 (11)
C22	0.0129 (13)	0.0147 (14)	0.0175 (15)	0.0010 (11)	−0.0006 (11)	−0.0043 (11)
C24	0.0238 (16)	0.0141 (14)	0.0148 (14)	−0.0062 (12)	0.0030 (12)	0.0008 (11)
N51	0.0297 (18)	0.0194 (15)	0.033 (2)	0.0054 (12)	0.0170 (15)	0.0012 (12)
C52	0.0133 (14)	0.0149 (14)	0.0193 (16)	0.0033 (11)	0.0000 (12)	−0.0024 (12)
N53	0.0308 (16)	0.0194 (12)	0.0284 (17)	−0.0060 (12)	0.0141 (13)	−0.0038 (11)
C54	0.0228 (17)	0.0163 (15)	0.0286 (18)	−0.0019 (13)	0.0079 (14)	0.0054 (14)
N100	0.0173 (12)	0.0121 (11)	0.0197 (12)	−0.0023 (10)	−0.0051 (9)	0.0019 (10)
C101	0.0271 (18)	0.0238 (17)	0.0300 (19)	−0.0022 (14)	−0.0017 (14)	−0.0083 (14)
C102	0.040 (2)	0.037 (2)	0.058 (3)	0.0070 (18)	0.0062 (19)	−0.019 (2)
C103	0.0198 (15)	0.0241 (16)	0.0243 (17)	−0.0068 (13)	−0.0047 (12)	0.0014 (13)
C104	0.036 (2)	0.0275 (18)	0.032 (2)	−0.0112 (15)	−0.0030 (15)	0.0106 (15)
C105	0.0258 (17)	0.0258 (17)	0.032 (2)	0.0015 (14)	−0.0039 (14)	0.0150 (14)
C106	0.032 (2)	0.043 (2)	0.061 (3)	−0.0080 (18)	−0.0004 (19)	0.032 (2)
C107	0.0222 (16)	0.0209 (16)	0.0240 (17)	0.0016 (13)	−0.0073 (13)	0.0006 (13)
C108	0.0326 (19)	0.039 (2)	0.033 (2)	0.0088 (16)	−0.0046 (16)	−0.0140 (17)
N200	0.0141 (12)	0.0192 (13)	0.0138 (12)	0.0007 (10)	−0.0027 (9)	0.0002 (10)
C201	0.0300 (17)	0.0254 (16)	0.0189 (16)	−0.0012 (14)	−0.0043 (13)	0.0007 (13)
C202	0.0338 (19)	0.0223 (16)	0.0275 (18)	0.0004 (14)	0.0110 (14)	0.0011 (14)
C203	0.0188 (15)	0.0259 (16)	0.0217 (16)	0.0006 (12)	−0.0073 (12)	0.0003 (13)
C204	0.0212 (16)	0.0268 (17)	0.0224 (17)	−0.0044 (13)	0.0004 (13)	−0.0068 (13)
C205	0.0183 (16)	0.0301 (17)	0.033 (2)	0.0053 (13)	−0.0045 (14)	−0.0056 (15)
C206	0.0223 (16)	0.0280 (17)	0.0312 (18)	−0.0002 (13)	0.0074 (13)	−0.0048 (15)
C207	0.0259 (17)	0.0192 (16)	0.0239 (17)	0.0022 (13)	−0.0015 (14)	0.0019 (12)
C208	0.0305 (18)	0.0243 (17)	0.0290 (18)	−0.0061 (14)	−0.0002 (14)	−0.0082 (15)

Geometric parameters (Å, º) top

Co1—O1	2.094 (2)	C101—C102	1.522 (5)
Co1—N15ⁱ	2.099 (2)	C101—H10A	0.9900
Co1—N6	2.113 (2)	C101—H10B	0.9900
Co1—N20ⁱⁱ	2.114 (3)	C102—H10C	0.9800
Co1—N5	2.114 (3)	C102—H10D	0.9800
Co1—O2	2.116 (2)	C102—H10E	0.9800
Co2—N11	2.099 (2)	C103—C104	1.523 (5)
Co2—N10	2.105 (2)	C103—H10F	0.9900
Co2—N16	2.107 (3)	C103—H10G	0.9900
Co2—N21	2.109 (3)	C104—H10H	0.9800
Co2—O3	2.116 (2)	C104—H10I	0.9800
Co2—O4	2.126 (2)	C104—H10J	0.9800
O1—H1A	0.79 (5)	C105—C106	1.517 (5)
O1—H1B	0.71 (4)	C105—H10K	0.9900
O2—H2A	0.84 (4)	C105—H10L	0.9900
O2—H2B	0.71 (4)	C106—H10M	0.9800
O3—H3A	0.77 (4)	C106—H10N	0.9800
O3—H3B	0.84 (6)	C106—H10O	0.9800
O4—H4A	0.74 (4)	C107—C108	1.512 (5)
O4—H4B	0.77 (5)	C107—H10P	0.9900
N1—C2	1.149 (5)	C107—H10Q	0.9900
N3—C2	1.278 (9)	C108—H10R	0.9800
N3—C4	1.307 (9)	C108—H10S	0.9800
N3'—C4	1.334 (6)	C108—H10T	0.9800
N3'—C2	1.335 (6)	N200—C203	1.515 (4)
N5—C4	1.149 (4)	N200—C205	1.516 (4)
N6—C7	1.160 (4)	N200—C201	1.518 (4)
N8—C7	1.308 (4)	N200—C207	1.539 (4)
N8—C9	1.309 (4)	C201—C202	1.532 (5)
N10—C9	1.158 (4)	C201—H20A	0.9900
N11—C12	1.157 (4)	C201—H20B	0.9900
N13—C12	1.308 (4)	C202—H20C	0.9800
N13—C14	1.314 (4)	C202—H20D	0.9800
N15—C14	1.145 (4)	C202—H20E	0.9800
N15—Co1ⁱⁱⁱ	2.099 (2)	C203—C204	1.524 (4)
N16—C17	1.151 (4)	C203—H20F	0.9900
N18—C19	1.309 (4)	C203—H20G	0.9900
N18—C17	1.312 (4)	C204—H20H	0.9800
N20—C19	1.155 (4)	C204—H20I	0.9800
N20—Co1^iv	2.114 (3)	C204—H20J	0.9800
N21—C22	1.148 (4)	C205—C206	1.516 (5)
N23—C24	1.304 (4)	C205—H20K	0.9900
N23—C22	1.324 (4)	C205—H20L	0.9900
N25—C24	1.161 (5)	C206—H20M	0.9800
N51—C52	1.162 (5)	C206—H20N	0.9800
C52—N53	1.301 (4)	C206—H20O	0.9800
N53—C54	1.290 (4)	C207—C208	1.518 (5)
C54—N55	1.159 (8)	C207—H20P	0.9900
C54—N56	1.176 (9)	C207—H20Q	0.9900
N100—C103	1.513 (4)	C208—H20R	0.9800
N100—C101	1.517 (4)	C208—H20S	0.9800
N100—C105	1.520 (4)	C208—H20T	0.9800
N100—C107	1.524 (4)

O1—Co1—N15ⁱ	91.39 (10)	N100—C103—C104	115.1 (3)
O1—Co1—N6	90.28 (10)	N100—C103—H10F	108.5
N15ⁱ—Co1—N6	178.10 (10)	C104—C103—H10F	108.5
O1—Co1—N20ⁱⁱ	89.81 (11)	N100—C103—H10G	108.5
N15ⁱ—Co1—N20ⁱⁱ	91.57 (10)	C104—C103—H10G	108.5
N6—Co1—N20ⁱⁱ	87.54 (10)	H10F—C103—H10G	107.5
O1—Co1—N5	88.62 (11)	C103—C104—H10H	109.5
N15ⁱ—Co1—N5	94.04 (10)	C103—C104—H10I	109.5
N6—Co1—N5	86.90 (11)	H10H—C104—H10I	109.5
N20ⁱⁱ—Co1—N5	174.22 (11)	C103—C104—H10J	109.5
O1—Co1—O2	178.90 (11)	H10H—C104—H10J	109.5
N15ⁱ—Co1—O2	88.25 (10)	H10I—C104—H10J	109.5
N6—Co1—O2	90.09 (10)	C106—C105—N100	114.8 (3)
N20ⁱⁱ—Co1—O2	91.25 (10)	C106—C105—H10K	108.6
N5—Co1—O2	90.36 (10)	N100—C105—H10K	108.6
N11—Co2—N10	178.97 (11)	C106—C105—H10L	108.6
N11—Co2—N16	91.79 (10)	N100—C105—H10L	108.6
N10—Co2—N16	89.21 (10)	H10K—C105—H10L	107.6
N11—Co2—N21	88.68 (11)	C105—C106—H10M	109.5
N10—Co2—N21	90.32 (11)	C105—C106—H10N	109.5
N16—Co2—N21	179.42 (12)	H10M—C106—H10N	109.5
N11—Co2—O3	89.94 (9)	C105—C106—H10O	109.5
N10—Co2—O3	89.81 (10)	H10M—C106—H10O	109.5
N16—Co2—O3	90.95 (10)	H10N—C106—H10O	109.5
N21—Co2—O3	89.38 (10)	C108—C107—N100	115.4 (3)
N11—Co2—O4	92.49 (10)	C108—C107—H10P	108.4
N10—Co2—O4	87.74 (9)	N100—C107—H10P	108.4
N16—Co2—O4	90.26 (10)	C108—C107—H10Q	108.4
N21—Co2—O4	89.39 (10)	N100—C107—H10Q	108.4
O3—Co2—O4	177.25 (10)	H10P—C107—H10Q	107.5
Co1—O1—H1A	117 (3)	C107—C108—H10R	109.5
Co1—O1—H1B	112 (3)	C107—C108—H10S	109.5
H1A—O1—H1B	111 (5)	H10R—C108—H10S	109.5
Co1—O2—H2A	110 (2)	C107—C108—H10T	109.5
Co1—O2—H2B	110 (3)	H10R—C108—H10T	109.5
H2A—O2—H2B	107 (4)	H10S—C108—H10T	109.5
Co2—O3—H3A	113 (3)	C203—N200—C205	111.1 (2)
Co2—O3—H3B	101 (4)	C203—N200—C201	111.6 (2)
H3A—O3—H3B	112 (5)	C205—N200—C201	107.5 (2)
Co2—O4—H4A	108 (3)	C203—N200—C207	106.4 (2)
Co2—O4—H4B	113 (3)	C205—N200—C207	110.6 (3)
H4A—O4—H4B	108 (5)	C201—N200—C207	109.6 (2)
C2—N3—C4	126.2 (7)	N200—C201—C202	114.3 (3)
C4—N3'—C2	119.5 (6)	N200—C201—H20A	108.7
C4—N5—Co1	153.4 (2)	C202—C201—H20A	108.7
C7—N6—Co1	174.2 (2)	N200—C201—H20B	108.7
C7—N8—C9	119.2 (2)	C202—C201—H20B	108.7
C9—N10—Co2	177.4 (2)	H20A—C201—H20B	107.6
C12—N11—Co2	170.1 (2)	C201—C202—H20C	109.5
C12—N13—C14	122.9 (3)	C201—C202—H20D	109.5
C14—N15—Co1ⁱⁱⁱ	171.5 (2)	H20C—C202—H20D	109.5
C17—N16—Co2	173.0 (2)	C201—C202—H20E	109.5
C19—N18—C17	122.0 (3)	H20C—C202—H20E	109.5
C19—N20—Co1^iv	164.3 (2)	H20D—C202—H20E	109.5
C22—N21—Co2	168.5 (3)	N200—C203—C204	113.3 (3)
C24—N23—C22	120.3 (3)	N200—C203—H20F	108.9
N1—C2—N3	168.3 (10)	C204—C203—H20F	108.9
N1—C2—N3'	168.5 (5)	N200—C203—H20G	108.9
N5—C4—N3	167.7 (9)	C204—C203—H20G	108.9
N5—C4—N3'	168.6 (5)	H20F—C203—H20G	107.7
N6—C7—N8	174.4 (3)	C203—C204—H20H	109.5
N10—C9—N8	174.4 (3)	C203—C204—H20I	109.5
N11—C12—N13	172.4 (3)	H20H—C204—H20I	109.5
N15—C14—N13	171.8 (3)	C203—C204—H20J	109.5
N16—C17—N18	172.7 (3)	H20H—C204—H20J	109.5
N20—C19—N18	173.3 (3)	H20I—C204—H20J	109.5
N21—C22—N23	173.7 (3)	N200—C205—C206	115.0 (3)
N25—C24—N23	173.5 (4)	N200—C205—H20K	108.5
N51—C52—N53	173.0 (3)	C206—C205—H20K	108.5
C54—N53—C52	121.7 (3)	N200—C205—H20L	108.5
N55—C54—N53	165.8 (7)	C206—C205—H20L	108.5
N56—C54—N53	166.1 (8)	H20K—C205—H20L	107.5
C103—N100—C101	110.9 (3)	C205—C206—H20M	109.5
C103—N100—C105	106.6 (2)	C205—C206—H20N	109.5
C101—N100—C105	111.7 (2)	H20M—C206—H20N	109.5
C103—N100—C107	111.4 (2)	C205—C206—H20O	109.5
C101—N100—C107	106.4 (2)	H20M—C206—H20O	109.5
C105—N100—C107	109.9 (3)	H20N—C206—H20O	109.5
N100—C101—C102	114.9 (3)	C208—C207—N200	114.2 (3)
N100—C101—H10A	108.5	C208—C207—H20P	108.7
C102—C101—H10A	108.5	N200—C207—H20P	108.7
N100—C101—H10B	108.5	C208—C207—H20Q	108.7
C102—C101—H10B	108.5	N200—C207—H20Q	108.7
H10A—C101—H10B	107.5	H20P—C207—H20Q	107.6
C101—C102—H10C	109.5	C207—C208—H20R	109.5
C101—C102—H10D	109.5	C207—C208—H20S	109.5
H10C—C102—H10D	109.5	H20R—C208—H20S	109.5
C101—C102—H10E	109.5	C207—C208—H20T	109.5
H10C—C102—H10E	109.5	H20R—C208—H20T	109.5
H10D—C102—H10E	109.5	H20S—C208—H20T	109.5

C4—N3—C2—N1	132 (2)	C107—N100—C105—C106	−58.1 (4)
C4—N3'—C2—N1	−148.8 (18)	C103—N100—C107—C108	60.6 (4)
Co1—N5—C4—N3	−39 (3)	C101—N100—C107—C108	−178.4 (3)
Co1—N5—C4—N3'	73 (2)	C105—N100—C107—C108	−57.3 (4)
C2—N3—C4—N5	−131.3 (19)	C203—N200—C201—C202	55.9 (3)
C2—N3'—C4—N5	154.7 (17)	C205—N200—C201—C202	178.0 (3)
C52—N53—C54—N55	114 (2)	C207—N200—C201—C202	−61.7 (3)
C52—N53—C54—N56	−118 (2)	C205—N200—C203—C204	−59.1 (4)
C103—N100—C101—C102	−55.4 (4)	C201—N200—C203—C204	60.9 (3)
C105—N100—C101—C102	63.4 (4)	C207—N200—C203—C204	−179.6 (3)
C107—N100—C101—C102	−176.7 (3)	C203—N200—C205—C206	−57.3 (4)
C101—N100—C103—C104	−58.1 (4)	C201—N200—C205—C206	−179.7 (3)
C105—N100—C103—C104	−180.0 (3)	C207—N200—C205—C206	60.6 (4)
C107—N100—C103—C104	60.2 (4)	C203—N200—C207—C208	179.3 (3)
C103—N100—C105—C106	−178.8 (3)	C205—N200—C207—C208	58.5 (4)
C101—N100—C105—C106	59.8 (4)	C201—N200—C207—C208	−59.9 (4)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N25^v	0.79 (5)	2.08 (5)	2.862 (4)	168 (4)
O1—H1B···N55ⁱⁱ	0.71 (4)	2.09 (4)	2.792 (7)	168 (4)
O1—H1B···N56ⁱⁱ	0.71 (4)	2.22 (4)	2.922 (9)	170 (4)
O2—H2A···N25^vi	0.84 (4)	2.03 (4)	2.862 (4)	172 (3)
O2—H2B···N55^vii	0.71 (4)	2.27 (4)	2.963 (8)	169 (4)
O2—H2B···N56^vii	0.71 (4)	2.12 (4)	2.819 (8)	171 (4)
O3—H3A···N51	0.77 (4)	2.07 (4)	2.822 (4)	165 (4)
O3—H3B···N1^viii	0.84 (6)	2.09 (6)	2.904 (4)	162 (5)
O4—H4A···N51^ix	0.74 (4)	2.23 (4)	2.958 (4)	172 (4)
O4—H4B···N1^x	0.77 (5)	2.07 (5)	2.833 (4)	169 (5)
C105—H10L···N18^v	0.99	2.57	3.439 (5)	146
C202—H20E···N8^xi	0.98	2.60	3.579 (5)	173
C204—H20H···N53^ix	0.98	2.49	3.316 (4)	142

Symmetry codes: (ii) x, −y+2, z−1/2; (v) x−1/2, y+1/2, z; (vi) x−1/2, y−1/2, z; (vii) x, −y+1, z−1/2; (viii) x+1/2, y−1/2, z; (ix) x, y+1, z; (x) x+1/2, y+1/2, z; (xi) x, y−1, z.

Acknowledgements

CL wishes to acknowledge the financial support for this work from the Research & Development Corporation of Newfoundland and Labrador. KAA wishes to acknowledge the National Science Foundation and the University of Florida for funding the purchase of the X-ray equipment.

References

Batten, S. R. & Murray, K. S. (2003). Coord. Chem. Rev. 246, 103–130. Web of Science CrossRef CAS Google Scholar
Biswas, M., Batten, S. R., Jensen, P. & Mitra, S. (2006). Aust. J. Chem. 59, 115–117. Web of Science CSD CrossRef CAS Google Scholar
Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Kurmoo, M. & Kepert, C. J. (1998). New J. Chem. 22, 1515–1524. Web of Science CSD CrossRef CAS Google Scholar
Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249–259. Web of Science CrossRef CAS IUCr Journals Google Scholar
Rajan, D., Quintero, P. A., Abboud, K. A., Meisel, M. W. & Talham, D. R. (2013). Polyhedron, 66, 142–146. CSD CrossRef CAS Google Scholar
Schlueter, J. A., Manson, J. L. & Geiser, U. (2005). Inorg. Chem. 44, 3194–3202. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Tong, M. L., Ru, J., Wu, Y. M., Chen, X. M., Chang, H. C., Mochizuki, K. & Kitagawa, S. (2003). New J. Chem. 27, 779–782. Web of Science CSD CrossRef CAS Google Scholar
Werff, P. M. van der, Batten, S. R., Jensen, P., Moubaraki, B., Murray, K. S. & Tan, E. H. K. (2001). Polyhedron, 20, 1129–1138. Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar

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