metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Poly[trans-di­aquabis­[μ2-2-(pyridin-3-yl)acetato-κ2N:O]­zinc]

aSchool of Chemical Science and Engineering, Yunnan University, Kunming 650091, People's Republic of China, and bSchool of Pharmacy, Dali University, Dali 671000, People's Republic of China
*Correspondence e-mail: qhzhao@ynu.edu.cn

(Received 7 September 2011; accepted 19 September 2011; online 30 September 2011)

In the title coordination polymer, [Zn(C7H6NO2)2(H2O)2]n, the ZnII cation is located on an inversion center and is coordinated by four pyridyl­acetate anions and two water mol­ecules in a distorted ZnN2O4 octa­hedral geometry. The pyridine-N and carboxyl­ate-O atoms of the pyridyl­acetate anion connect to two ZnII cations, forming a two-dimensional polymeric complex extending parallel to (212). Inter­molecular O—H⋯O and weak C—H⋯O hydrogen bonding is present in the crystal structure.

Related literature

For related complexes with pyridyl­acetate ligands, see: Li et al. (2004[Li, X., Cao, R., Sun, Y.-Q., Shi, Q., Yuan, D.-Q., Sun, D.-F., Bi, W.-H. & Hong, M.-C. (2004). Cryst. Growth Des. 4, 255-261.]); Du et al. (2006[Du, M., Li, C.-P. & Zhao, X.-J. (2006). Cryst. Growth Des. 6, 335-341.]); Martin et al. (2007[Martin, D. P., Springsteen, C. H. & LaDuca, R. L. (2007). Inorg. Chim. Acta, 360, 599-606.]); Qin et al. (2007[Qin, S.-N., Liang, F.-P., Chen, Z.-L. & Yan, W.-H. (2007). Acta Cryst. E63, m1492-m1493.]); Aakeröy et al. (1999[Aakeröy, C. B., Beatty, A. M. & Leinen, D. S. (1999). Angew. Chem. Int. Ed. 38, 1815-1819.]); Evans & Lin (2002[Evans, O. R. & Lin, W. B. (2002). Acc. Chem. Res. 35, 511-522.]); Tong et al. (2003[Tong, M.-L., Li, L.-J., Mochizuki, K., Chang, H.-C., Chen, X.-M., Li, Y. & Kitagawa, S. (2003). Chem. Commun. pp. 428-429.]).

[Scheme 1]

Experimental

Crystal data
  • [Zn(C7H6NO2)2(H2O)2]

  • Mr = 373.66

  • Monoclinic, P 21 /n

  • a = 9.175 (2) Å

  • b = 8.686 (2) Å

  • c = 9.574 (2) Å

  • β = 105.928 (3)°

  • V = 733.8 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.71 mm−1

  • T = 298 K

  • 0.20 × 0.20 × 0.19 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Brucker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.718, Tmax = 0.723

  • 4934 measured reflections

  • 1732 independent reflections

  • 1178 reflections with I > 2σ(I)

  • Rint = 0.054

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.098

  • S = 1.00

  • 1732 reflections

  • 112 parameters

  • 3 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Selected bond lengths (Å)

Zn1—N1 2.168 (3)
Zn1—O2i 2.091 (2)
Zn1—O3 2.125 (2)
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3B⋯O1i 0.81 (3) 1.99 (3) 2.739 (4) 152 (4)
O3—H3C⋯O1ii 0.82 (3) 1.97 (3) 2.764 (4) 161 (3)
C1—H1A⋯O1iii 0.93 2.54 3.443 (5) 163
C3—H3A⋯O1iv 0.93 2.50 3.366 (5) 155
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) -x+1, -y, -z+1; (iii) x, y, z-1; (iv) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Brucker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Brucker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The compounds of pyridine-carboxylic acids have been extensively utilized in the preparation of metal complexes due to their versatile coordination modes. Though various metal-pyridinepolycarboxylate complexes have been reported (Evans et al., 2002; Aakeröy et al., 1999; Li et al., 2004; Du et al., 2006), 3-pyridylacetate complexes are rare. Only a few of complexes as nickel, cobalt and copper species have been combined up to now (Martin et al., 2007). In this paper, we described a new two-dimensional coordination polymer, [Zn(3-pyridylacetato)2(H2O)2]n, (I). The molecular structure of the title complex is similar to those previously reported such as [M(4-pyridylacetato)2(H2O)2]n (M = Cu, Co, Mn, Ni, Zn, Cd)(Du et al., 2006; Qin et al., 2007; Tong et al., 2003) and [M(3-pyridylacetato)2(H2O)2]n (M = Ni, Co, Cu) (Martin et al., 2007;). Single-crystal X-ray diffraction analysis shows that the title compound is crystallized in a space group P21/n. The ZnII center is six-coordinated by two water molecules in the axial positions, two pyridyl nitrogen atoms and two carboxylate oxygen atoms from two 3-pyridylacetate ligands in the plane. Pyridine nitrogen atom and carboxylate oxygen atom of each 3-pyridylacetate anion are connected to one ZnII ions. The coordination geometry of ZnII cation can been described as a distorted octahedral geometry with Zn—N and Zn—O distance range 2.168 (2) Å and 2.091 (3)—2.125 (3) Å, respectively (Fig. 1, Table 1). Four 3-pyridylacetate anionic ligands and four ZnII ions are combined to a tetragon, which is of a side length of 8.653 Å and a diagonal measurement of 14.969*8.686 Å based on the Zn—Zn distances. The tetragon is further extended into a two-dimensional framework structure parallel to (212) with arhombic grid through sharing ZnII ions, 3-pyridylacetate anionic ligands. Adjacent two-dimensional layers are connected by the intermolecular O—H···O and weak C—H···O hydrogen-bonding contacts, forming a three-dimensional framework structure with oxygen as a trifurcated acceptor atom (Fig. 2)

Related literature top

For related complexes with pyridylacetate ligands, see: Li et al. (2004); Du et al. (2006); Martin et al. (2007); Qin et al. (2007); Aakeröy et al. (1999); Evans & Lin (2002); Tong et al. (2003).

Experimental top

A mixture of Zn(COO)2.H2O (0.1 mmol), 3-pyridyl acetic acid (0.1 mmol), DMF (5.0 ml) and methanol (10.0 ml) was stirred for 30 min and and the crude product was isolated by filtration. The filtrate was purified by recrystallization from anhydrous methanol and DMF to give (I) as colorless block crystals in 60% yield. An solution of (I) was stood at room temperature, and upon slowly evaporating methanol and DMF from the solution, colorless block crystals suitable for X-ray diffraction analysis were isolated in room temperature three week later.

Refinement top

Water H atoms were located in a difference Fourier map and positional parameters were refined, Uiso(H) = 1.2Ueq(O). Other H atoms were generated geometrically and were included in therefinement in the riding model approximation with C—H = 0.93–0.97 Å, Uiso= 1.2Ueq(C).

Structure description top

The compounds of pyridine-carboxylic acids have been extensively utilized in the preparation of metal complexes due to their versatile coordination modes. Though various metal-pyridinepolycarboxylate complexes have been reported (Evans et al., 2002; Aakeröy et al., 1999; Li et al., 2004; Du et al., 2006), 3-pyridylacetate complexes are rare. Only a few of complexes as nickel, cobalt and copper species have been combined up to now (Martin et al., 2007). In this paper, we described a new two-dimensional coordination polymer, [Zn(3-pyridylacetato)2(H2O)2]n, (I). The molecular structure of the title complex is similar to those previously reported such as [M(4-pyridylacetato)2(H2O)2]n (M = Cu, Co, Mn, Ni, Zn, Cd)(Du et al., 2006; Qin et al., 2007; Tong et al., 2003) and [M(3-pyridylacetato)2(H2O)2]n (M = Ni, Co, Cu) (Martin et al., 2007;). Single-crystal X-ray diffraction analysis shows that the title compound is crystallized in a space group P21/n. The ZnII center is six-coordinated by two water molecules in the axial positions, two pyridyl nitrogen atoms and two carboxylate oxygen atoms from two 3-pyridylacetate ligands in the plane. Pyridine nitrogen atom and carboxylate oxygen atom of each 3-pyridylacetate anion are connected to one ZnII ions. The coordination geometry of ZnII cation can been described as a distorted octahedral geometry with Zn—N and Zn—O distance range 2.168 (2) Å and 2.091 (3)—2.125 (3) Å, respectively (Fig. 1, Table 1). Four 3-pyridylacetate anionic ligands and four ZnII ions are combined to a tetragon, which is of a side length of 8.653 Å and a diagonal measurement of 14.969*8.686 Å based on the Zn—Zn distances. The tetragon is further extended into a two-dimensional framework structure parallel to (212) with arhombic grid through sharing ZnII ions, 3-pyridylacetate anionic ligands. Adjacent two-dimensional layers are connected by the intermolecular O—H···O and weak C—H···O hydrogen-bonding contacts, forming a three-dimensional framework structure with oxygen as a trifurcated acceptor atom (Fig. 2)

For related complexes with pyridylacetate ligands, see: Li et al. (2004); Du et al. (2006); Martin et al. (2007); Qin et al. (2007); Aakeröy et al. (1999); Evans & Lin (2002); Tong et al. (2003).

Computing details top

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

Figures top
[Figure 1] Fig. 1. The molecular structure of the title complex with the atom-numbering diagram. Ellipsoids were drawn at the 30% probability level.
[Figure 2] Fig. 2. The packing diagram of (I).
Poly[trans-diaquabis[µ2-2-(pyridin-3-yl)acetato- κ2N,O]zinc] top
Crystal data top
[Zn(C7H6NO2)2(H2O)2]F(000) = 384
Mr = 373.66Dx = 1.691 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4934 reflections
a = 9.175 (2) Åθ = 3.2–28.2°
b = 8.686 (2) ŵ = 1.71 mm1
c = 9.574 (2) ÅT = 298 K
β = 105.928 (3)°Block, colorless
V = 733.8 (3) Å30.20 × 0.20 × 0.19 mm
Z = 2
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1732 independent reflections
Radiation source: fine-focus sealed tube1178 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
φ and ω scansθmax = 28.2°, θmin = 3.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1211
Tmin = 0.718, Tmax = 0.723k = 1111
4934 measured reflectionsl = 912
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)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.035P)2 + 0.2786P]
where P = (Fo2 + 2Fc2)/3
1732 reflections(Δ/σ)max < 0.001
112 parametersΔρmax = 0.39 e Å3
3 restraintsΔρmin = 0.38 e Å3
Crystal data top
[Zn(C7H6NO2)2(H2O)2]V = 733.8 (3) Å3
Mr = 373.66Z = 2
Monoclinic, P21/nMo Kα radiation
a = 9.175 (2) ŵ = 1.71 mm1
b = 8.686 (2) ÅT = 298 K
c = 9.574 (2) Å0.20 × 0.20 × 0.19 mm
β = 105.928 (3)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
1732 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
1178 reflections with I > 2σ(I)
Tmin = 0.718, Tmax = 0.723Rint = 0.054
4934 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0423 restraints
wR(F2) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.39 e Å3
1732 reflectionsΔρmin = 0.38 e Å3
112 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
Zn10.50000.00000.00000.02624 (18)
O10.2006 (3)0.1719 (3)0.6106 (3)0.0400 (6)
O20.0333 (3)0.2812 (3)0.4230 (2)0.0331 (6)
O30.6282 (3)0.0534 (3)0.2153 (3)0.0359 (6)
H3C0.694 (3)0.002 (3)0.272 (3)0.043*
H3B0.676 (4)0.130 (3)0.207 (4)0.043*
N10.3007 (3)0.0777 (3)0.0596 (3)0.0293 (6)
C10.1913 (4)0.1572 (4)0.0326 (4)0.0346 (8)
H1A0.20320.18140.12350.042*
C20.0611 (4)0.2054 (4)0.0003 (4)0.0372 (9)
H2A0.01230.26120.06700.045*
C30.0414 (4)0.1699 (4)0.1341 (4)0.0346 (8)
H3A0.04600.20040.15780.042*
C40.1537 (4)0.0881 (4)0.2333 (3)0.0267 (7)
C50.2802 (4)0.0449 (4)0.1900 (4)0.0295 (8)
H5A0.35570.01040.25550.035*
C60.1407 (4)0.0437 (4)0.3815 (4)0.0341 (9)
H6A0.22960.01580.43020.041*
H6B0.05320.02290.36920.041*
C70.1255 (4)0.1768 (4)0.4799 (4)0.0278 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.0299 (3)0.0285 (3)0.0225 (3)0.0017 (3)0.0111 (2)0.0004 (2)
O10.0477 (16)0.0369 (14)0.0309 (14)0.0064 (12)0.0033 (12)0.0006 (11)
O20.0417 (15)0.0324 (13)0.0259 (12)0.0088 (11)0.0106 (11)0.0015 (10)
O30.0426 (16)0.0340 (14)0.0279 (14)0.0022 (12)0.0044 (11)0.0018 (11)
N10.0336 (17)0.0316 (16)0.0256 (15)0.0012 (13)0.0130 (12)0.0007 (12)
C10.045 (2)0.034 (2)0.0261 (18)0.0034 (17)0.0126 (16)0.0024 (15)
C20.037 (2)0.039 (2)0.034 (2)0.0102 (17)0.0060 (16)0.0004 (16)
C30.029 (2)0.037 (2)0.039 (2)0.0047 (16)0.0121 (16)0.0065 (17)
C40.033 (2)0.0232 (18)0.0263 (17)0.0001 (14)0.0123 (15)0.0021 (14)
C50.034 (2)0.0275 (18)0.0286 (18)0.0025 (14)0.0116 (15)0.0035 (14)
C60.048 (2)0.0259 (18)0.035 (2)0.0059 (16)0.0234 (17)0.0035 (14)
C70.0286 (19)0.0282 (18)0.0314 (19)0.0034 (15)0.0160 (15)0.0037 (15)
Geometric parameters (Å, º) top
Zn1—N12.168 (3)C1—C21.382 (5)
Zn1—N1i2.168 (3)C1—H1A0.9300
Zn1—O2ii2.091 (2)C2—C31.377 (5)
Zn1—O2iii2.091 (2)C2—H2A0.9300
Zn1—O32.125 (2)C3—C41.390 (5)
O1—C71.252 (4)C3—H3A0.9300
O2—C71.258 (4)C4—C51.387 (4)
O2—Zn1iv2.091 (2)C4—C61.507 (4)
O3—H3C0.825 (18)C5—H5A0.9300
O3—H3B0.812 (17)C6—C71.522 (4)
N1—C11.333 (4)C6—H6A0.9700
N1—C51.344 (4)C6—H6B0.9700
O2ii—Zn1—O2iii180.00 (12)C1—C2—H2A120.4
O2ii—Zn1—O3i87.23 (9)C2—C3—C4119.2 (3)
O2iii—Zn1—O3i92.77 (9)C2—C3—H3A120.4
O2ii—Zn1—N1i88.57 (10)C4—C3—H3A120.4
O2iii—Zn1—N1i91.43 (10)C5—C4—C3117.3 (3)
O3i—Zn1—N1i87.67 (10)C5—C4—C6120.1 (3)
O2ii—Zn1—N191.43 (10)C3—C4—C6122.6 (3)
O2iii—Zn1—N188.57 (10)N1—C5—C4124.2 (3)
O3i—Zn1—N192.33 (10)N1—C5—H5A117.9
N1i—Zn1—N1180.00 (12)C4—C5—H5A117.9
C7—O2—Zn1iv130.4 (2)C4—C6—C7115.7 (3)
H3C—O3—H3B101 (2)C4—C6—H6A108.4
C1—N1—C5117.0 (3)C7—C6—H6A108.4
C1—N1—Zn1121.5 (2)C4—C6—H6B108.4
C5—N1—Zn1121.5 (2)C7—C6—H6B108.4
N1—C1—C2123.1 (3)H6A—C6—H6B107.4
N1—C1—H1A118.4O1—C7—O2125.3 (3)
C2—C1—H1A118.4O1—C7—C6118.3 (3)
C3—C2—C1119.1 (3)O2—C7—C6116.4 (3)
C3—C2—H2A120.4
Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y1/2, z+1/2; (iv) x+1/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3B···O1ii0.81 (3)1.99 (3)2.739 (4)152 (4)
O3—H3C···O1v0.82 (3)1.97 (3)2.764 (4)161 (3)
C1—H1A···O1vi0.932.543.443 (5)163
C3—H3A···O1vii0.932.503.366 (5)155
Symmetry codes: (ii) x+1/2, y+1/2, z1/2; (v) x+1, y, z+1; (vi) x, y, z1; (vii) x1/2, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formula[Zn(C7H6NO2)2(H2O)2]
Mr373.66
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)9.175 (2), 8.686 (2), 9.574 (2)
β (°) 105.928 (3)
V3)733.8 (3)
Z2
Radiation typeMo Kα
µ (mm1)1.71
Crystal size (mm)0.20 × 0.20 × 0.19
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.718, 0.723
No. of measured, independent and
observed [I > 2σ(I)] reflections
4934, 1732, 1178
Rint0.054
(sin θ/λ)max1)0.665
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.098, 1.00
No. of reflections1732
No. of parameters112
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.39, 0.38

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

Selected bond lengths (Å) top
Zn1—N12.168 (3)Zn1—O32.125 (2)
Zn1—O2i2.091 (2)
Symmetry code: (i) x+1/2, y+1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3B···O1i0.81 (3)1.99 (3)2.739 (4)152 (4)
O3—H3C···O1ii0.82 (3)1.97 (3)2.764 (4)161 (3)
C1—H1A···O1iii0.932.543.443 (5)163
C3—H3A···O1iv0.932.503.366 (5)155
Symmetry codes: (i) x+1/2, y+1/2, z1/2; (ii) x+1, y, z+1; (iii) x, y, z1; (iv) x1/2, y+1/2, z1/2.
 

Acknowledgements

This work was supported by the Natural Science Foundation of Yunan Province, China (grant 2009 CD015).

References

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