supplementary materials


bt2766 scheme

Acta Cryst. (2008). E64, m1158    [ doi:10.1107/S1600536808025622 ]

Tetraaqua(1,10-phenanthroline)zinc(II) 3,6-dicarboxybicyclo[2.2.2]oct-7-ene-2,5-dicarboxylate

C.-H. Yu

Abstract top

In the title compound, [Zn(C12H8N2)(H2O)4](C12H10O8), each ZnII atom is six-coordinated by two N atoms from one phenanthroline molecule and by four O atoms from four water molecules in a distorted octahedral environment. In the crystal structure, ions are linked by O-H...O hydrogen bonds.

Comment top

Recently, complexes with poly(carboxylic acids) have been investigated in the area of solid state and material science (Ma et al., 2003). I selected bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid (H4L) as a poly(carboxylic acid) ligand and phenanthroline (phen) as a secondary ligand, generating a new complex, [Zn(phen)(H2O)4].[H2L], which is reported here.

In the title compound, [Zn(phen)(H2O)4].[H2L], each ZnII atom is six-coordinated by two N atoms from one phen molecule, and four O atoms from four water molecules in a distorted octahedral environment. Each H2L2- acts as a counter-anion. In the crystal, the molecules are linked by O—H···O hydrogen bonds.

Related literature top

For related literature, see: Ma et al. (2003); Hu (2008).

Experimental top

A mixture of H4L (0.5 mmol), phen (0.5 mmol), NaOH (1 mmol) and ZnCl2.6H2O (0.5 mmol) was suspended in 12 ml of deionized water and sealed in a 20-ml Teflon-lined autoclave. Upon heating at 140°C for one week, the autoclave was slowly cooled to room temperature. The crystals were collected, washed with deionized water and dried.

Refinement top

All H atoms on C atoms were positioned geometrically (C—H = 0.93 Å) and refined as riding, with Uiso(H)=1.2Ueq(carrier). The water H-atoms were located in a difference Fourier map, and were refined with distance restraints of O–H = 0.85±0.01 Å; their displacement parameters were set to 1.2Ueq(O).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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 the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
Tetraaqua(1,10-phenanthroline)zinc(II) 3,6-dicarboxybicyclo[2.2.2]oct-7-ene-2,5-dicarboxylate top
Crystal data top
[Zn(C12H8N2)(H2O)4](C12H10O8)F000 = 1240
Mr = 599.84Dx = 1.711 Mg m3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5626 reflections
a = 7.4550 (2) Åθ = 1.1–28.3º
b = 13.5991 (4) ŵ = 1.13 mm1
c = 22.9833 (7) ÅT = 293 (2) K
β = 91.5550 (10)ºBlock, colorless
V = 2329.22 (12) Å30.33 × 0.22 × 0.19 mm
Z = 4
Data collection top
Bruker APEX CCD area-detector
diffractometer
5626 independent reflections
Radiation source: fine-focus sealed tube3854 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.048
T = 293(2) Kθmax = 28.3º
φ and ω scansθmin = 1.7º
Absorption correction: multi-scan
(SAINT; Bruker, 1998)
h = 9→8
Tmin = 0.687, Tmax = 0.805k = 14→18
14301 measured reflectionsl = 29→30
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.046H atoms treated by a mixture of
independent and constrained refinement
wR(F2) = 0.122  w = 1/[σ2(Fo2) + (0.0613P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.96(Δ/σ)max < 0.001
5626 reflectionsΔρmax = 0.50 e Å3
382 parametersΔρmin = 0.59 e Å3
12 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
[Zn(C12H8N2)(H2O)4](C12H10O8)V = 2329.22 (12) Å3
Mr = 599.84Z = 4
Monoclinic, P21/cMo Kα
a = 7.4550 (2) ŵ = 1.13 mm1
b = 13.5991 (4) ÅT = 293 (2) K
c = 22.9833 (7) Å0.33 × 0.22 × 0.19 mm
β = 91.5550 (10)º
Data collection top
Bruker APEX CCD area-detector
diffractometer
5626 independent reflections
Absorption correction: multi-scan
(SAINT; Bruker, 1998)
3854 reflections with I > 2σ(I)
Tmin = 0.687, Tmax = 0.805Rint = 0.048
14301 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.04612 restraints
wR(F2) = 0.122H atoms treated by a mixture of
independent and constrained refinement
S = 0.96Δρmax = 0.50 e Å3
5626 reflectionsΔρmin = 0.59 e Å3
382 parameters
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.2556 (4)0.2855 (2)0.61401 (12)0.0348 (7)
H10.25290.22640.63440.042*
C20.2659 (4)0.3745 (3)0.64532 (13)0.0414 (8)
H20.27080.37340.68570.050*
C40.2686 (5)0.4609 (3)0.61680 (15)0.0459 (9)
H40.27560.51940.63760.055*
C50.2610 (5)0.4632 (2)0.55588 (14)0.0399 (8)
C60.2629 (6)0.5510 (2)0.52184 (18)0.0570 (10)
H60.26280.61170.54050.068*
C70.2648 (6)0.5479 (2)0.46388 (18)0.0554 (10)
H70.26920.60640.44300.067*
C80.2603 (5)0.4564 (2)0.43289 (15)0.0385 (8)
C90.2666 (4)0.4472 (2)0.37212 (14)0.0409 (8)
H90.27270.50320.34890.049*
C100.2639 (4)0.3579 (2)0.34720 (13)0.0377 (8)
H100.26940.35230.30690.045*
C110.2527 (4)0.2731 (2)0.38191 (12)0.0307 (7)
H110.25020.21180.36410.037*
C120.2538 (4)0.3703 (2)0.52783 (12)0.0272 (6)
C130.2518 (4)0.3674 (2)0.46512 (12)0.0271 (6)
C140.1068 (4)0.06219 (19)0.70078 (12)0.0268 (6)
C150.2475 (4)0.12469 (19)0.73318 (11)0.0220 (6)
H150.32950.08080.75480.026*
C160.3605 (4)0.19231 (18)0.69329 (10)0.0206 (5)
H160.48690.17840.70270.025*
C170.3320 (4)0.1720 (2)0.62817 (11)0.0252 (6)
C180.3279 (3)0.30060 (18)0.70964 (10)0.0187 (5)
H180.38940.34450.68290.022*
C190.1500 (4)0.19201 (18)0.77770 (11)0.0209 (5)
H190.07440.15240.80290.025*
C200.0380 (4)0.26442 (19)0.74361 (11)0.0243 (6)
H200.08570.26920.74690.029*
C0210.2081 (4)0.3018 (2)0.86562 (11)0.0234 (6)
C210.1303 (4)0.32112 (19)0.70833 (11)0.0245 (6)
H210.07730.36930.68490.029*
C220.4016 (4)0.31473 (18)0.77246 (11)0.0211 (5)
H220.52460.28920.77320.025*
C230.4151 (4)0.4227 (2)0.79029 (11)0.0262 (6)
C250.2936 (4)0.24790 (18)0.81443 (10)0.0216 (6)
H250.37710.19900.83090.026*
N10.2458 (3)0.27831 (16)0.43985 (9)0.0246 (5)
N20.2495 (3)0.28378 (17)0.55612 (9)0.0255 (5)
O10.2699 (3)0.23710 (15)0.59560 (8)0.0417 (6)
O20.3860 (3)0.08866 (14)0.60983 (8)0.0348 (5)
O1W0.4920 (3)0.13197 (19)0.49279 (10)0.0375 (5)
O30.1019 (3)0.02720 (15)0.72076 (9)0.0469 (6)
H30.02550.05870.70240.070*
O2W0.1668 (4)0.06205 (18)0.43708 (11)0.0422 (6)
O40.0122 (3)0.09170 (16)0.66157 (10)0.0473 (6)
O3W0.2116 (4)0.0585 (2)0.56396 (12)0.0490 (6)
O50.3699 (3)0.49114 (14)0.76039 (9)0.0399 (5)
O4W0.0517 (3)0.17941 (19)0.50606 (9)0.0401 (6)
O60.4927 (3)0.42964 (15)0.84189 (8)0.0374 (5)
H6A0.49950.48770.85140.056*
O70.2531 (3)0.27139 (14)0.91541 (8)0.0336 (5)
O80.0968 (3)0.36877 (15)0.85579 (8)0.0371 (5)
Zn10.22063 (5)0.16487 (2)0.499735 (13)0.02916 (12)
HW220.223 (4)0.013 (2)0.4325 (16)0.063 (13)*
HW410.113 (5)0.198 (3)0.5355 (10)0.095*
HW210.092 (4)0.069 (3)0.4124 (14)0.074 (15)*
HW420.109 (4)0.195 (2)0.4781 (9)0.037 (10)*
HW120.551 (4)0.168 (2)0.4714 (11)0.043 (11)*
HW110.551 (5)0.118 (3)0.5214 (12)0.079 (15)*
HW310.282 (6)0.057 (3)0.5893 (17)0.119*
HW320.195 (6)0.009 (2)0.5475 (17)0.083 (18)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0317 (17)0.049 (2)0.0242 (14)0.0001 (14)0.0003 (12)0.0013 (14)
C20.0318 (18)0.067 (2)0.0255 (15)0.0106 (16)0.0019 (13)0.0162 (16)
C40.043 (2)0.049 (2)0.0447 (19)0.0084 (16)0.0065 (16)0.0268 (17)
C50.045 (2)0.0296 (17)0.0447 (19)0.0040 (14)0.0066 (15)0.0126 (15)
C60.079 (3)0.0198 (17)0.072 (3)0.0021 (16)0.007 (2)0.0094 (18)
C70.074 (3)0.0221 (18)0.070 (3)0.0012 (17)0.004 (2)0.0069 (17)
C80.044 (2)0.0230 (16)0.0478 (19)0.0010 (13)0.0031 (15)0.0094 (14)
C90.041 (2)0.0408 (19)0.0404 (18)0.0060 (15)0.0033 (15)0.0234 (15)
C100.0336 (18)0.054 (2)0.0251 (15)0.0009 (14)0.0010 (13)0.0107 (15)
C110.0318 (16)0.0369 (17)0.0235 (14)0.0024 (13)0.0001 (12)0.0001 (13)
C120.0309 (16)0.0223 (14)0.0283 (15)0.0003 (11)0.0022 (12)0.0038 (12)
C130.0319 (16)0.0208 (14)0.0283 (14)0.0005 (11)0.0027 (12)0.0022 (12)
C140.0353 (17)0.0180 (14)0.0273 (14)0.0034 (11)0.0054 (13)0.0008 (11)
C150.0283 (15)0.0176 (13)0.0201 (13)0.0006 (10)0.0004 (11)0.0004 (10)
C160.0236 (14)0.0201 (13)0.0180 (12)0.0012 (10)0.0012 (11)0.0023 (10)
C170.0331 (16)0.0264 (15)0.0161 (12)0.0042 (12)0.0006 (11)0.0004 (11)
C180.0241 (14)0.0152 (12)0.0167 (12)0.0037 (10)0.0017 (10)0.0019 (10)
C190.0234 (14)0.0178 (13)0.0218 (13)0.0028 (10)0.0054 (11)0.0012 (10)
C200.0220 (14)0.0252 (14)0.0255 (14)0.0014 (11)0.0029 (11)0.0002 (11)
C0210.0296 (15)0.0219 (14)0.0188 (13)0.0019 (11)0.0028 (11)0.0009 (11)
C210.0279 (15)0.0220 (14)0.0233 (13)0.0030 (11)0.0051 (11)0.0010 (11)
C220.0233 (14)0.0196 (13)0.0203 (13)0.0002 (10)0.0001 (11)0.0007 (10)
C230.0341 (16)0.0241 (15)0.0204 (13)0.0099 (12)0.0031 (12)0.0014 (11)
C250.0248 (14)0.0187 (13)0.0213 (13)0.0027 (10)0.0006 (11)0.0001 (11)
N10.0286 (13)0.0241 (12)0.0212 (11)0.0011 (10)0.0006 (9)0.0011 (10)
N20.0282 (13)0.0278 (13)0.0203 (11)0.0000 (10)0.0019 (9)0.0015 (10)
O10.0729 (17)0.0249 (11)0.0264 (10)0.0026 (10)0.0152 (11)0.0063 (9)
O20.0529 (14)0.0266 (11)0.0248 (10)0.0048 (9)0.0025 (10)0.0068 (9)
O1W0.0282 (12)0.0574 (16)0.0270 (12)0.0047 (11)0.0014 (10)0.0052 (11)
O30.0640 (17)0.0305 (12)0.0454 (13)0.0204 (11)0.0111 (12)0.0083 (10)
O2W0.0487 (16)0.0325 (14)0.0457 (14)0.0005 (11)0.0034 (12)0.0171 (11)
O40.0527 (15)0.0370 (13)0.0507 (14)0.0078 (11)0.0267 (12)0.0000 (11)
O3W0.0611 (18)0.0372 (15)0.0482 (15)0.0090 (12)0.0082 (13)0.0157 (13)
O50.0610 (16)0.0250 (11)0.0330 (11)0.0052 (10)0.0117 (10)0.0037 (9)
O4W0.0259 (12)0.0736 (18)0.0208 (10)0.0078 (11)0.0007 (9)0.0006 (11)
O60.0551 (15)0.0235 (11)0.0328 (11)0.0068 (9)0.0142 (10)0.0010 (9)
O70.0495 (14)0.0329 (12)0.0184 (9)0.0085 (10)0.0031 (9)0.0025 (8)
O80.0507 (14)0.0341 (12)0.0267 (11)0.0174 (10)0.0063 (10)0.0014 (9)
Zn10.0328 (2)0.0265 (2)0.0280 (2)0.00085 (14)0.00117 (14)0.00085 (14)
Geometric parameters (Å, °) top
C1—N21.333 (3)C18—C211.499 (4)
C1—C21.410 (4)C18—C221.543 (3)
C1—H10.9300C18—H180.9800
C2—C41.346 (5)C19—C201.498 (4)
C2—H20.9300C19—C251.545 (4)
C4—C51.403 (5)C19—H190.9800
C4—H40.9300C20—C211.325 (4)
C5—C121.420 (4)C20—H200.9300
C5—C61.428 (5)C021—O81.248 (3)
C6—C71.333 (6)C021—O71.254 (3)
C6—H60.9300C021—C251.539 (3)
C7—C81.434 (5)C21—H210.9300
C7—H70.9300C22—C231.526 (3)
C8—C91.402 (4)C22—C251.564 (3)
C8—C131.419 (4)C22—H220.9800
C9—C101.343 (4)C23—O51.200 (3)
C9—H90.9300C23—O61.309 (3)
C10—C111.403 (4)C25—H250.9800
C10—H100.9300N1—Zn12.073 (2)
C11—N11.333 (3)N2—Zn12.087 (2)
C11—H110.9300O1W—Zn12.074 (2)
C12—N21.344 (3)O1W—HW120.816 (17)
C12—C131.442 (4)O1W—HW110.826 (18)
C13—N11.345 (3)O3—H30.8200
C14—O41.198 (3)O2W—Zn12.055 (2)
C14—O31.300 (3)O2W—HW220.799 (17)
C14—C151.528 (4)O2W—HW210.809 (17)
C15—C161.561 (3)O3W—Zn12.067 (2)
C15—C191.567 (3)O3W—HW310.80 (4)
C15—H150.9800O3W—HW320.784 (18)
C16—C171.531 (3)O4W—Zn12.041 (2)
C16—C181.541 (3)O4W—HW410.845 (18)
C16—H160.9800O4W—HW420.811 (17)
C17—O11.240 (3)O6—H6A0.8200
C17—O21.279 (3)
N2—C1—C2121.9 (3)C20—C19—H19110.4
N2—C1—H1119.1C25—C19—H19110.4
C2—C1—H1119.1C15—C19—H19110.4
C4—C2—C1120.0 (3)C21—C20—C19114.3 (2)
C4—C2—H2120.0C21—C20—H20122.9
C1—C2—H2120.0C19—C20—H20122.9
C2—C4—C5120.3 (3)O8—C021—O7124.5 (2)
C2—C4—H4119.8O8—C021—C25119.8 (2)
C5—C4—H4119.8O7—C021—C25115.7 (2)
C4—C5—C12115.9 (3)C20—C21—C18113.9 (2)
C4—C5—C6124.4 (3)C20—C21—H21123.0
C12—C5—C6119.7 (3)C18—C21—H21123.0
C7—C6—C5121.4 (3)C23—C22—C18113.0 (2)
C7—C6—H6119.3C23—C22—C25115.1 (2)
C5—C6—H6119.3C18—C22—C25109.2 (2)
C6—C7—C8121.7 (3)C23—C22—H22106.3
C6—C7—H7119.2C18—C22—H22106.3
C8—C7—H7119.2C25—C22—H22106.3
C9—C8—C13116.4 (3)O5—C23—O6124.9 (3)
C9—C8—C7124.9 (3)O5—C23—C22125.2 (2)
C13—C8—C7118.8 (3)O6—C23—C22109.7 (2)
C10—C9—C8120.3 (3)C021—C25—C19110.9 (2)
C10—C9—H9119.8C021—C25—C22115.2 (2)
C8—C9—H9119.8C19—C25—C22108.0 (2)
C9—C10—C11120.1 (3)C021—C25—H25107.5
C9—C10—H10119.9C19—C25—H25107.5
C11—C10—H10119.9C22—C25—H25107.5
N1—C11—C10121.6 (3)C11—N1—C13118.6 (2)
N1—C11—H11119.2C11—N1—Zn1128.64 (19)
C10—C11—H11119.2C13—N1—Zn1112.79 (17)
N2—C12—C5124.0 (3)C1—N2—C12117.8 (3)
N2—C12—C13117.4 (2)C1—N2—Zn1129.8 (2)
C5—C12—C13118.6 (3)C12—N2—Zn1112.28 (17)
N1—C13—C8123.0 (3)Zn1—O1W—HW12115 (2)
N1—C13—C12117.2 (2)Zn1—O1W—HW11122 (3)
C8—C13—C12119.8 (3)HW12—O1W—HW11109 (3)
O4—C14—O3123.8 (3)C14—O3—H3109.5
O4—C14—C15124.2 (2)Zn1—O2W—HW22124 (3)
O3—C14—C15111.9 (2)Zn1—O2W—HW21124 (3)
C14—C15—C16114.5 (2)HW22—O2W—HW21112 (3)
C14—C15—C19108.6 (2)Zn1—O3W—HW31122 (4)
C16—C15—C19107.85 (19)Zn1—O3W—HW32105 (3)
C14—C15—H15108.6HW31—O3W—HW32117 (3)
C16—C15—H15108.6Zn1—O4W—HW41127 (3)
C19—C15—H15108.6Zn1—O4W—HW42121 (2)
C17—C16—C18113.1 (2)HW41—O4W—HW42106 (3)
C17—C16—C15113.9 (2)C23—O6—H6A109.5
C18—C16—C15109.2 (2)O4W—Zn1—O2W84.42 (10)
C17—C16—H16106.7O4W—Zn1—O3W90.23 (10)
C18—C16—H16106.7O2W—Zn1—O3W91.20 (12)
C15—C16—H16106.7O4W—Zn1—N192.69 (9)
O1—C17—O2123.3 (2)O2W—Zn1—N193.26 (10)
O1—C17—C16120.1 (2)O3W—Zn1—N1174.89 (11)
O2—C17—C16116.4 (2)O4W—Zn1—O1W173.09 (10)
C21—C18—C16109.5 (2)O2W—Zn1—O1W90.46 (10)
C21—C18—C22108.7 (2)O3W—Zn1—O1W85.22 (10)
C16—C18—C22107.0 (2)N1—Zn1—O1W92.24 (9)
C21—C18—H18110.5O4W—Zn1—N290.00 (9)
C16—C18—H18110.5O2W—Zn1—N2171.08 (10)
C22—C18—H18110.5O3W—Zn1—N295.79 (11)
C20—C19—C25109.3 (2)N1—Zn1—N280.02 (9)
C20—C19—C15107.7 (2)O1W—Zn1—N295.62 (9)
C25—C19—C15108.5 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O8i0.821.882.674 (3)163
O6—H6A···O2ii0.821.842.583 (3)151
O2W—HW22···O2iii0.799 (17)2.06 (2)2.818 (3)158 (4)
O4W—HW41···O10.845 (18)1.86 (2)2.705 (3)174 (4)
O2W—HW21···O8iv0.809 (17)2.121 (18)2.904 (3)163 (4)
O4W—HW42···O7iv0.811 (17)1.876 (17)2.686 (3)177 (3)
O1W—HW12···O7v0.816 (17)2.09 (2)2.884 (3)165 (3)
O1W—HW11···O2vi0.826 (18)2.13 (2)2.923 (3)160 (4)
O3W—HW31···O2vi0.80 (4)2.57 (4)3.233 (4)142 (5)
Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) −x+1, y+1/2, −z+3/2; (iii) −x, −y, −z+1; (iv) x, −y+1/2, z−1/2; (v) x−1, −y+1/2, z−1/2; (vi) x−1, y, z.
Table 1
Hydrogen-bond geometry (Å, °)
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D—H···AD—HH···AD···AD—H···A
O3—H3···O8i0.821.882.674 (3)163
O6—H6A···O2ii0.821.842.583 (3)151
O2W—HW22···O2iii0.799 (17)2.06 (2)2.818 (3)158 (4)
O4W—HW41···O10.845 (18)1.86 (2)2.705 (3)174 (4)
O2W—HW21···O8iv0.809 (17)2.121 (18)2.904 (3)163 (4)
O4W—HW42···O7iv0.811 (17)1.876 (17)2.686 (3)177 (3)
O1W—HW12···O7v0.816 (17)2.09 (2)2.884 (3)165 (3)
O1W—HW11···O2vi0.826 (18)2.13 (2)2.923 (3)160 (4)
O3W—HW31···O2vi0.80 (4)2.57 (4)3.233 (4)142 (5)
Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) −x+1, y+1/2, −z+3/2; (iii) −x, −y, −z+1; (iv) x, −y+1/2, z−1/2; (v) x−1, −y+1/2, z−1/2; (vi) x−1, y, z.
Acknowledgements top

The authors thank Beihua University for supporting this work.

references
References top

Bruker (1998). SMART, SAINT and SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.

Hu, T. (2008). Acta Cryst. E64, o1021.

Ma, J.-F., Yang, J., Zheng, G.-L., Li, L. & Liu, J.-F. (2003). Inorg. Chem. 42, 7531–7534.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.