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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Bis(imidazo[4,5-f][1,10]phenanthroline)dinitratolead(II)

aSchool of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China, and bDepartment of Chemistry, Jilin Normal University, Siping 136000, People's Republic of China
*Correspondence e-mail: guangbochejl@yahoo.com

(Received 28 November 2008; accepted 7 December 2008; online 13 December 2008)

In the title compound, [Pb(NO3)2(C13H8N4)2], the PbII atom (site symmetry 2) is hexa­coordinated by four N atoms from two N,N′-bidentate imidazo[4,5-f][1,10]phenanthroline (L) ligands and two O atoms from two weakly coordinated nitrate ions [Pb—O = 2.872 (5) Å] in an irregular arrangement, which may be ascribed to the stereochemically active lone pair of electrons on the metal ion. In the crystal, inter­molecular bifurcated N—H⋯(O,O) hydrogen bonds connect the mol­ecules into chains propagating along [100]. Adjacent chains inter­act by strong aromatic ππ stacking inter­actions, with a centroid–centroid distance of 3.483 (2) Å.

Related literature

For the ligand synthesis, see: Steck & Day (1943[Steck, E. A. & Day, A. R. (1943). J. Am. Chem. Soc. 65, 452-456.]). For background, see: Che et al. (2006[Che, G.-B., Xu, Z.-L. & Liu, C.-B. (2006). Acta Cryst. E62, m1695-m1696.], 2008[Che, G.-B., Liu, C.-B., Liu, B., Wang, Q.-W. & Xu, Z.-L. (2008). CrystEngComm, 10, 184-191.]); Thomas et al. (2008[Thomas, C., Jan, R., Peter, N., Kris, D., Kristof, V. H., Luc, V. M., Shengbin, L., Steven, D. F., Daniel, G., Bertrand, D. & Koen, B. (2008). Chem. Mater. 20, 1278-1291.]); Xu et al. (2008[Xu, Z.-L., Li, X.-Y., Che, G.-B., Liu, C.-B. & Wang, Q.-W. (2008). Chin. J. Struct. Chem. 27, 593-597.]).

[Scheme 1]

Experimental

Crystal data
  • [Pb(NO3)2(C13H8N4)2]

  • Mr = 771.68

  • Monoclinic, C 2/c

  • a = 19.203 (4) Å

  • b = 7.3948 (15) Å

  • c = 17.392 (4) Å

  • β = 100.48 (3)°

  • V = 2428.5 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 7.02 mm−1

  • T = 292 (2) K

  • 0.56 × 0.22 × 0.11 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.165, Tmax = 0.453

  • 10060 measured reflections

  • 2402 independent reflections

  • 2170 reflections with I > 2σ(I)

  • Rint = 0.049

Refinement
  • R[F2 > 2σ(F2)] = 0.026

  • wR(F2) = 0.064

  • S = 1.05

  • 2402 reflections

  • 195 parameters

  • H-atom parameters constrained

  • Δρmax = 0.89 e Å−3

  • Δρmin = −0.63 e Å−3

Table 1
Selected bond lengths (Å)

Pb—N1 2.540 (3)
Pb—N2 2.606 (3)
Pb—O1 2.872 (5)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯O3i 0.86 2.19 3.030 (6) 165
N3—H3A⋯O2i 0.86 2.35 3.059 (6) 140
Symmetry code: (i) [-x+{\script{1\over 2}}, -y-{\script{1\over 2}}, -z].

Data collection: SMART (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

1,10-Phenanthroline and its derivatives are very important heteroaromatic N-donor chelating ligands for the construction of coordination compounds. (Che et al., 2008; Xu et al., 2008; Che et al., 2006). Whereas, only a handful of supramolecular architectures based on imidazo[4,5-f][1,10]phenanthroline ligand (L) have been described (Thomas et al., 2008). The present attempt at synthesizing a new lead complex with L ligand gave the title complex, [Pb(C13H8N4)2(NO3)2] (I), whose structure is reported here.

In the title compound I, each Pb atom is hexacoordinated by four N atoms (N1, N1i, N2, N2i) from two L ligand and two O (O1, O1i) atoms from two NO3- ions (Fig. 1). The Pb—N bond lengths are normal (Table 1), however, O1 and O1i could be described as being semicoordinated with long Pb—O lengths of 2.872 (5) Å. The PbN4O2 coordination polyhedron approximates a distorted octahedral configuration.

In the crystal structure, the mononuclear complex molecules are linked via intermolecular N—H···O and N—H··· N hydrogen bonds (Table 2) forming one-dimensional chains along [100] (Fig. 2). Withal, one-dimensional chains are stabilized by π-π interactions between the L rings planes of neighboring molecules with distances of 3.442 Å (Fig. 3), leading to a three-dimensional network.

Related literature top

For the ligand synthesis, see: Steck & Day (1943). For background, see: Che et al. (2006, 2008); Thomas et al. (2008); Xu et al. (2008). AUTHOR: Please supply missing Fig. 2

Experimental top

The L ligand was synthesized according to the literature method of Steck & Day (1943). A mixture of Pb(NO3)2 (0.5 mmol) and the ligand (1 mmol) was dissolved in 15 ml distilled water, then followed by addition of NaOH until the pH value of the system approximately 6.0. Finally the resulting solution was sealed into a 23 ml Teflon-lined stainless steel autoclave and heated at 413 K for 3 d under autogenous pressure. The reaction autoclave slowly cooled to room temperature, yielding yellow block-like crystals of (I) in 62% yield based on Pb.

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(C). The hydrogen atoms of water molecules were located from difference Fourier maps and their positions and Uiso values were refined freely.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXS97 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of (I). Displacement ellipsoids are drawn at the 30% probability level (arbitrary spheres for the H atoms). Dashed lines indicate semicoordinated bonds [Symmetry code: (i) -x + 1, y, -z + 1/2].
[Figure 2] Fig. 2. A packing diagram of the title compound, showing a one-dimensional chain-like structure generated by the intermolecular hydrogen bonding. H atoms have been omitted [Symmetry code: (A) -x + 1, -y - 1/2, z - 1/2].
Bis(imidazo[4,5-f][1,10]phenanthroline)dinitratolead(II) top
Crystal data top
[Pb(NO3)2(C13H8N4)2]F(000) = 1488
Mr = 771.68Dx = 2.111 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3904 reflections
a = 19.203 (4) Åθ = 2.2–26.1°
b = 7.3948 (15) ŵ = 7.02 mm1
c = 17.392 (4) ÅT = 292 K
β = 100.48 (3)°Block, yellow
V = 2428.5 (8) Å30.56 × 0.22 × 0.11 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer
2402 independent reflections
Radiation source: fine-focus sealed tube2170 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.049
ω scansθmax = 26.1°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
h = 2323
Tmin = 0.165, Tmax = 0.453k = 99
10060 measured reflectionsl = 2021
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)] = 0.026Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.064H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0304P)2]
where P = (Fo2 + 2Fc2)/3
2402 reflections(Δ/σ)max = 0.005
195 parametersΔρmax = 0.89 e Å3
0 restraintsΔρmin = 0.63 e Å3
Crystal data top
[Pb(NO3)2(C13H8N4)2]V = 2428.5 (8) Å3
Mr = 771.68Z = 4
Monoclinic, C2/cMo Kα radiation
a = 19.203 (4) ŵ = 7.02 mm1
b = 7.3948 (15) ÅT = 292 K
c = 17.392 (4) Å0.56 × 0.22 × 0.11 mm
β = 100.48 (3)°
Data collection top
Bruker SMART CCD
diffractometer
2402 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
2170 reflections with I > 2σ(I)
Tmin = 0.165, Tmax = 0.453Rint = 0.049
10060 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0260 restraints
wR(F2) = 0.064H-atom parameters constrained
S = 1.05Δρmax = 0.89 e Å3
2402 reflectionsΔρmin = 0.63 e Å3
195 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
C10.3676 (2)0.2885 (6)0.1841 (2)0.0361 (10)
H10.35760.26440.23340.043*
C20.3181 (3)0.3843 (7)0.1316 (3)0.0472 (12)
H20.27720.42830.14660.057*
C30.3303 (2)0.4130 (6)0.0577 (3)0.0411 (11)
H30.29730.47490.02140.049*
C40.3927 (2)0.3486 (5)0.0372 (2)0.0270 (9)
C50.4423 (2)0.2606 (5)0.0951 (2)0.0242 (8)
C60.5099 (2)0.1997 (5)0.0783 (2)0.0242 (8)
C70.6190 (2)0.0678 (6)0.1228 (3)0.0329 (9)
H70.65050.01170.16270.040*
C80.6394 (2)0.0921 (6)0.0507 (2)0.0354 (10)
H80.68450.05800.04390.043*
C90.4103 (2)0.3613 (5)0.0386 (2)0.0284 (9)
C100.5268 (2)0.2217 (5)0.0028 (2)0.0251 (8)
C110.4729 (2)0.2999 (5)0.0565 (2)0.0272 (9)
C120.4129 (3)0.3952 (6)0.1631 (2)0.0386 (11)
H120.39850.42530.21550.046*
C130.5931 (2)0.1660 (5)0.0100 (2)0.0296 (9)
H130.60550.17900.05900.035*
N50.2959 (2)0.1066 (5)0.1716 (2)0.0387 (9)
O20.2564 (2)0.0783 (8)0.2184 (3)0.0874 (14)
N10.42843 (17)0.2294 (4)0.16763 (18)0.0268 (7)
N20.55658 (17)0.1214 (4)0.13726 (18)0.0262 (7)
N30.3723 (2)0.4235 (5)0.1083 (2)0.0359 (8)
H3A0.33070.47110.11560.043*
N40.4751 (2)0.3210 (4)0.13538 (18)0.0341 (8)
O10.35914 (17)0.1449 (5)0.19411 (19)0.0508 (9)
O30.2706 (2)0.0901 (7)0.1014 (2)0.0747 (12)
Pb0.50000.01345 (3)0.25000.02722 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.034 (3)0.047 (2)0.030 (2)0.005 (2)0.013 (2)0.0003 (19)
C20.032 (3)0.068 (3)0.044 (3)0.018 (2)0.013 (2)0.006 (2)
C30.032 (3)0.055 (3)0.035 (3)0.017 (2)0.003 (2)0.008 (2)
C40.024 (2)0.0303 (19)0.026 (2)0.0021 (16)0.0025 (17)0.0008 (16)
C50.022 (2)0.0264 (18)0.024 (2)0.0013 (16)0.0046 (17)0.0018 (15)
C60.024 (2)0.0247 (18)0.023 (2)0.0014 (15)0.0024 (17)0.0016 (15)
C70.025 (2)0.041 (2)0.031 (2)0.0063 (19)0.0020 (19)0.0061 (18)
C80.027 (3)0.046 (2)0.035 (3)0.005 (2)0.010 (2)0.0001 (19)
C90.026 (2)0.032 (2)0.025 (2)0.0007 (17)0.0023 (18)0.0004 (16)
C100.023 (2)0.0264 (19)0.025 (2)0.0021 (17)0.0033 (16)0.0028 (15)
C110.032 (2)0.0283 (19)0.021 (2)0.0018 (17)0.0034 (17)0.0013 (15)
C120.047 (3)0.043 (2)0.022 (2)0.000 (2)0.003 (2)0.0042 (18)
C130.030 (2)0.041 (2)0.020 (2)0.0006 (18)0.0111 (18)0.0019 (16)
N50.035 (2)0.051 (2)0.030 (2)0.0030 (18)0.0059 (18)0.0036 (16)
O20.048 (3)0.171 (4)0.049 (3)0.009 (3)0.024 (2)0.008 (3)
N10.0184 (18)0.0355 (17)0.0273 (18)0.0007 (14)0.0065 (14)0.0000 (13)
N20.0235 (19)0.0331 (17)0.0217 (17)0.0045 (14)0.0031 (14)0.0022 (13)
N30.031 (2)0.0431 (19)0.032 (2)0.0073 (17)0.0007 (17)0.0029 (16)
N40.041 (2)0.0406 (19)0.0202 (18)0.0029 (17)0.0032 (16)0.0022 (14)
O10.0265 (19)0.068 (2)0.053 (2)0.0076 (16)0.0049 (16)0.0099 (17)
O30.054 (3)0.133 (4)0.034 (2)0.016 (3)0.0015 (19)0.009 (2)
Pb0.02505 (15)0.03545 (14)0.02129 (13)0.0000.00458 (9)0.000
Geometric parameters (Å, º) top
C1—N11.327 (5)C9—N31.376 (5)
C1—C21.387 (6)C10—C131.393 (6)
C1—H10.9300C10—C111.442 (5)
C2—C31.364 (6)C11—N41.390 (5)
C2—H20.9300C12—N41.323 (5)
C3—C41.396 (6)C12—N31.353 (6)
C3—H30.9300C12—H120.9300
C4—C51.413 (5)C13—H130.9300
C4—C91.423 (5)N5—O21.227 (5)
C5—N11.355 (5)N5—O31.235 (5)
C5—C61.453 (5)N5—O11.239 (5)
C6—N21.362 (5)Pb—N12.540 (3)
C6—C101.418 (5)Pb—N22.606 (3)
C7—N21.329 (5)Pb—O12.872 (5)
C7—C81.392 (6)N3—H3A0.8600
C7—H70.9300Pb—N1i2.540 (3)
C8—C131.365 (6)Pb—N2i2.606 (3)
C8—H80.9300O1—Pbi2.872 (5)
C9—C111.372 (6)
N1—C1—C2123.5 (4)C9—C11—N4111.8 (4)
N1—C1—H1118.3C9—C11—C10121.0 (3)
C2—C1—H1118.3N4—C11—C10127.1 (4)
C3—C2—C1119.0 (4)N4—C12—N3113.9 (4)
C3—C2—H2120.5N4—C12—H12123.0
C1—C2—H2120.5N3—C12—H12123.0
C2—C3—C4119.4 (4)C8—C13—C10118.7 (4)
C2—C3—H3120.3C8—C13—H13120.6
C4—C3—H3120.3C10—C13—H13120.6
C3—C4—C5118.3 (4)O2—N5—O3117.3 (4)
C3—C4—C9125.0 (4)O2—N5—O1121.2 (4)
C5—C4—C9116.6 (4)O3—N5—O1121.4 (4)
N1—C5—C4121.4 (3)C1—N1—C5118.4 (3)
N1—C5—C6118.0 (3)C1—N1—Pb121.2 (3)
C4—C5—C6120.7 (3)C5—N1—Pb117.9 (2)
N2—C6—C10121.1 (4)C7—N2—C6118.5 (3)
N2—C6—C5118.0 (3)C7—N2—Pb122.8 (3)
C10—C6—C5120.9 (3)C6—N2—Pb115.0 (2)
N2—C7—C8122.9 (4)C12—N3—C9106.7 (4)
N2—C7—H7118.6C12—N3—H3A126.7
C8—C7—H7118.6C9—N3—H3A126.7
C13—C8—C7119.9 (4)C12—N4—C11102.6 (4)
C13—C8—H8120.1N1—Pb—N1i90.01 (14)
C7—C8—H8120.1N1—Pb—N2i84.09 (10)
C11—C9—N3105.0 (3)N1i—Pb—N2i64.03 (10)
C11—C9—C4123.6 (4)N1—Pb—N264.03 (10)
N3—C9—C4131.4 (4)N1i—Pb—N284.09 (10)
C13—C10—C6118.9 (4)N2i—Pb—N2135.02 (14)
C13—C10—C11124.2 (3)O1—Pb—N170.65 (10)
C6—C10—C11116.9 (4)O1—Pb—N2111.75 (10)
N1—C1—C2—C33.2 (7)C11—C10—C13—C8179.3 (4)
C1—C2—C3—C41.2 (7)C2—C1—N1—C51.6 (6)
C2—C3—C4—C52.1 (7)C2—C1—N1—Pb163.1 (4)
C2—C3—C4—C9176.7 (4)C4—C5—N1—C12.0 (5)
C3—C4—C5—N13.8 (6)C6—C5—N1—C1178.4 (3)
C9—C4—C5—N1175.1 (3)C4—C5—N1—Pb160.2 (3)
C3—C4—C5—C6176.6 (4)C6—C5—N1—Pb19.5 (4)
C9—C4—C5—C64.5 (5)C8—C7—N2—C61.5 (6)
N1—C5—C6—N22.6 (5)C8—C7—N2—Pb158.6 (3)
C4—C5—C6—N2177.7 (3)C10—C6—N2—C70.9 (5)
N1—C5—C6—C10177.6 (3)C5—C6—N2—C7178.9 (3)
C4—C5—C6—C102.0 (5)C10—C6—N2—Pb157.9 (3)
N2—C7—C8—C133.2 (7)C5—C6—N2—Pb22.3 (4)
C3—C4—C9—C11178.6 (4)N4—C12—N3—C90.6 (5)
C5—C4—C9—C112.6 (6)C11—C9—N3—C120.5 (4)
C3—C4—C9—N34.8 (7)C4—C9—N3—C12176.5 (4)
C5—C4—C9—N3173.9 (4)N3—C12—N4—C110.4 (5)
N2—C6—C10—C131.6 (5)C9—C11—N4—C120.1 (4)
C5—C6—C10—C13178.1 (3)C10—C11—N4—C12178.9 (4)
N2—C6—C10—C11177.7 (3)C1—N1—Pb—N1i93.6 (3)
C5—C6—C10—C112.5 (5)C5—N1—Pb—N1i104.8 (3)
N3—C9—C11—N40.2 (4)C1—N1—Pb—N2i29.7 (3)
C4—C9—C11—N4177.1 (4)C5—N1—Pb—N2i168.7 (3)
N3—C9—C11—C10179.3 (3)C1—N1—Pb—N2177.0 (3)
C4—C9—C11—C102.0 (6)C5—N1—Pb—N221.4 (2)
C13—C10—C11—C9176.2 (4)C7—N2—Pb—N1179.9 (3)
C6—C10—C11—C94.5 (5)C6—N2—Pb—N122.2 (2)
C13—C10—C11—N44.9 (6)C7—N2—Pb—N1i87.2 (3)
C6—C10—C11—N4174.4 (4)C6—N2—Pb—N1i115.1 (3)
C7—C8—C13—C102.3 (6)C7—N2—Pb—N2i130.6 (3)
C6—C10—C13—C80.0 (6)C6—N2—Pb—N2i71.7 (2)
Symmetry code: (i) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O3ii0.862.193.030 (6)165
N3—H3A···O2ii0.862.353.059 (6)140
Symmetry code: (ii) x+1/2, y1/2, z.

Experimental details

Crystal data
Chemical formula[Pb(NO3)2(C13H8N4)2]
Mr771.68
Crystal system, space groupMonoclinic, C2/c
Temperature (K)292
a, b, c (Å)19.203 (4), 7.3948 (15), 17.392 (4)
β (°) 100.48 (3)
V3)2428.5 (8)
Z4
Radiation typeMo Kα
µ (mm1)7.02
Crystal size (mm)0.56 × 0.22 × 0.11
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2002)
Tmin, Tmax0.165, 0.453
No. of measured, independent and
observed [I > 2σ(I)] reflections
10060, 2402, 2170
Rint0.049
(sin θ/λ)max1)0.619
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.026, 0.064, 1.05
No. of reflections2402
No. of parameters195
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.89, 0.63

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Pb—N12.540 (3)Pb—O12.872 (5)
Pb—N22.606 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O3i0.862.193.030 (6)165
N3—H3A···O2i0.862.353.059 (6)140
Symmetry code: (i) x+1/2, y1/2, z.
 

Acknowledgements

The authors thank the Natural Science Foundation of Jiangsu University and the Natural Science Foundation of Jilin Normal University for support.

References

First citationBruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChe, G.-B., Liu, C.-B., Liu, B., Wang, Q.-W. & Xu, Z.-L. (2008). CrystEngComm, 10, 184–191.  Web of Science CSD CrossRef CAS Google Scholar
First citationChe, G.-B., Xu, Z.-L. & Liu, C.-B. (2006). Acta Cryst. E62, m1695–m1696.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSteck, E. A. & Day, A. R. (1943). J. Am. Chem. Soc. 65, 452–456.  CrossRef CAS Google Scholar
First citationThomas, C., Jan, R., Peter, N., Kris, D., Kristof, V. H., Luc, V. M., Shengbin, L., Steven, D. F., Daniel, G., Bertrand, D. & Koen, B. (2008). Chem. Mater. 20, 1278–1291.  Web of Science CrossRef Google Scholar
First citationXu, Z.-L., Li, X.-Y., Che, G.-B., Liu, C.-B. & Wang, Q.-W. (2008). Chin. J. Struct. Chem. 27, 593–597.  CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds