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Acta Crystallogr Sect E Struct Rep Online. 2008 December 1; 64(Pt 12): m1552.
Published online 2008 November 13. doi:  10.1107/S1600536808036726
PMCID: PMC2959936

Tetra-n-butyl­ammonium bis­(1,1-dicyano­ethyl­ene-2,2-dithiol­ato)platinum(II)

Abstract

In the title compound, (C16H36N)2[Pt(C4N2S2)2], the PtII center adopts a distorted square-planar geometry due to the 4-membered chelate rings formed by coordination to the S atoms of the 1,1-dicyano­ethyl­ene-2,2-dithiol­ate (i-mnt) ligands [bite angle 74.35 (4)°]. The bond distances in the coordinated i-mnt ligands indicate some delocalization of the π-system.

Related literature

For general background on the salts of metal complexes of [Pt(i-mnt)2]2− (i-mnt=1,1-dicyano­ethyl­ene-2,2-dithiol­ate), see: Cummings & Eisenberg (1996 [triangle]); Fackler & Coucouvanis (1966 [triangle]); Werden et al. (1966 [triangle]). For related structures, see: Gao et al. (2005 [triangle], 2006 [triangle]); Hummel (1987 [triangle]); Li et al. (2004 [triangle]); Sun et al. (2006 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-m1552-scheme1.jpg

Experimental

Crystal data

  • (C16H36N)2[Pt(C4N2S2)2]
  • M r = 960.40
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-m1552-efi1.jpg
  • a = 9.8687 (6) Å
  • b = 16.9556 (11) Å
  • c = 13.8274 (9) Å
  • β = 92.840 (1)°
  • V = 2310.9 (3) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 3.25 mm−1
  • T = 173 (2) K
  • 0.40 × 0.20 × 0.15 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker 2003 [triangle]) T min = 0.468, T max = 0.612
  • 22256 measured reflections
  • 4087 independent reflections
  • 3226 reflections with I > 2σ(I)
  • R int = 0.033

Refinement

  • R[F 2 > 2σ(F 2)] = 0.027
  • wR(F 2) = 0.077
  • S = 1.09
  • 4087 reflections
  • 236 parameters
  • H-atom parameters constrained
  • Δρmax = 1.02 e Å−3
  • Δρmin = −0.33 e Å−3

Data collection: SMART (Bruker,2003 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808036726/pk2127sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808036726/pk2127Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by funding from the NSF through a Research Site for Educators in Chemistry grant. The authors acknowledge Victor G. Young, Jr and the X-ray Crystallographic Laboratory in the Department of Chemistry at the University of Minnesota.

supplementary crystallographic information

Comment

Salts of metal complexes of [Pt(i-mnt)2]2- (i-mnt=1,1-dicyanoethylene-2,2-dithiolate) have been studied for their interesting electronic properties including their photoluminescence (Cummings & Eisenberg, 1996) and their redox behavior especially in relation to the analagous isomeric ligand 1,2-dicyanoethylene-1,2-dithiolate (mnt2-) complexes (Fackler & Coucouvanis, 1966; Werden et al., 1966). In sharp contrast to mnt complexes of the form [M(mnt)2]2- (M= NiII, PdII, PtII) which do exhibit reversible oxidation behavior, analagous i-mnt complexes of the form [M(i-mnt)2]2- do not. This effect is attributed to better π-delocalization of the five-membered rings formed by complexation of mnt compared with four-membered chelate rings of i-mnt complexes. Salts of [Pt(i-mnt)2]2- have also been studied as supramolecular linker groups in organic-inorganic hybrid coordination polymers (Gao et al. 2005, 2006; Li et al. 2004; Sun et al. 2006). While several x-ray structures of [Pt(i-mnt)2]2- with alkali metal-complexed crown ether salts have been reported, only one other simple non-coordinating cation salt (tetraethylammonium, Hummel 1987) has been structurally characterized.

The structure of the anion in the title compound (C16H36N)2[Pt(S2C4N2)2] shows significant distortions from a square planar environment as forced by the four-membered chelate rings of the i-mnt ligands, with the i-mnt bite angle S(2)—Pt(1)—S(1) = 74.35 (4)°. As the Pt sits on the special position (1/2,1/2,1/2) in the space group P21/n, Z'=0.5. The anion is quite planar, with a calculated r.m.s. deviation from a least-squares plane formed by all atoms of the complex anion of 0.042 (3) Å. The bond lengths within coordinated i-mnt ligand, in particular the bonds C(1)—C(2) 1.361 (6) Å, C(2)—C(3) 1.429 (6) Å, and C(2)—C(4) 1.430 (6)Å are very similar to those observed in the tetraethylammonium salt, showing significant π-delocalization. No columnar stacking is observed amongst the complex anions. As expected, upon comparison of the structure of the title compound and the tetraethylammonium salt, little effect was observed on the intramolecular features of the complex anion.

Experimental

The title compound (C16H36N)2[Pt(S2C4N2)2] was prepared using a procedure similar to that described by Fackler and Coucouvanis (1966) subsituting the use of tetra-n-propylammonium iodide with tetra-n-butylammonium bromide. The title compound has been previously characterized by Werden et al.(1966). Spectroscopic analysis of the present sample obtained by this procedure was consistent with the data previously reported. Crystals were obtained by diffusion of diethyl ether into a concentrated solution of the title compound dissolved in dichloromethane.

Refinement

The H atoms were geometrically placed (C—H = 0.98–0.99 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).

Figures

Fig. 1.
The molecular structure of (C16H36N)2[Pt(S2C4N2)2] showing 50% displacement ellipsoids for the non-hydrogen atoms. Only the crystallographically independent atoms are labelled.

Crystal data

(C16H36N)2[Pt(C4N2S2)2]F000 = 992
Mr = 960.40Dx = 1.380 Mg m3
Monoclinic, P21/nMo Kα radiation λ = 0.71069 Å
Hall symbol: -P 2ynCell parameters from 3207 reflections
a = 9.8687 (6) Åθ = 5.5–50.0º
b = 16.9556 (11) ŵ = 3.25 mm1
c = 13.8274 (9) ÅT = 173 (2) K
β = 92.840 (1)ºPlate, yellow
V = 2310.9 (3) Å30.4 × 0.2 × 0.15 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer4087 independent reflections
Radiation source: normal-focus sealed tube3226 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.033
T = 173(2) Kθmax = 25.1º
[var phi] scansθmin = 1.9º
Absorption correction: multi-scan(SADABS; Bruker 2003)h = −11→11
Tmin = 0.468, Tmax = 0.612k = −20→20
22256 measured reflectionsl = −16→16

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.077  w = 1/[σ2(Fo2) + (0.0339P)2 + 3.6638P] where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max = 0.001
4087 reflectionsΔρmax = 1.02 e Å3
236 parametersΔρmin = −0.33 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

Special details

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)

xyzUiso*/Ueq
Pt10.50000.50000.50000.03643 (9)
S10.56122 (11)0.43791 (7)0.64610 (8)0.0434 (3)
S20.30447 (11)0.49674 (7)0.58620 (8)0.0439 (2)
C10.3957 (4)0.4489 (2)0.6793 (3)0.0365 (9)
C20.3440 (4)0.4241 (2)0.7636 (3)0.0395 (9)
C30.2028 (5)0.4321 (2)0.7797 (3)0.0432 (10)
C40.4294 (5)0.3889 (2)0.8383 (3)0.0419 (10)
N10.0899 (4)0.4381 (3)0.7927 (3)0.0585 (11)
N20.4951 (5)0.3608 (2)0.8982 (3)0.0558 (10)
N30.6156 (3)0.15041 (17)0.7976 (2)0.0311 (7)
C50.6718 (4)0.0849 (2)0.7366 (3)0.0325 (8)
H5A0.59980.04490.72500.039*
H5B0.74710.05920.77470.039*
C60.7239 (5)0.1092 (3)0.6392 (3)0.0513 (12)
H6A0.64730.12840.59650.062*
H6B0.78990.15280.64850.062*
C70.7915 (5)0.0399 (3)0.5914 (3)0.0530 (12)
H7A0.83700.05940.53380.064*
H7B0.86260.01850.63720.064*
C80.6986 (7)−0.0250 (4)0.5610 (5)0.088 (2)
H8A0.7497−0.06640.52930.131*
H8B0.6276−0.00470.51560.131*
H8C0.6568−0.04700.61800.131*
C90.7213 (4)0.2133 (2)0.8215 (3)0.0364 (9)
H9A0.67950.25390.86200.044*
H9B0.74460.23910.76030.044*
C100.8523 (4)0.1859 (2)0.8736 (3)0.0407 (10)
H10A0.83170.16240.93680.049*
H10B0.89540.14480.83460.049*
C110.9494 (5)0.2548 (3)0.8897 (3)0.0454 (10)
H11A0.96510.27960.82640.054*
H11B0.90630.29470.93050.054*
C121.0841 (5)0.2320 (3)0.9372 (4)0.0548 (12)
H12A1.14390.27810.94080.082*
H12B1.12560.19050.89910.082*
H12C1.07060.21241.00270.082*
C130.5705 (4)0.1106 (2)0.8892 (3)0.0321 (8)
H13A0.50590.06800.87030.039*
H13B0.65070.08550.92230.039*
C140.5040 (5)0.1638 (2)0.9614 (3)0.0416 (10)
H14A0.56850.20560.98340.050*
H14B0.42340.18960.92970.050*
C150.4618 (4)0.1166 (2)1.0474 (3)0.0389 (9)
H15A0.54340.09221.07940.047*
H15B0.40070.07361.02420.047*
C160.3900 (5)0.1654 (3)1.1214 (3)0.0499 (11)
H16A0.35990.13091.17290.075*
H16B0.31120.19161.08970.075*
H16C0.45260.20521.14920.075*
C170.4978 (4)0.1918 (2)0.7443 (3)0.0354 (9)
H17A0.46890.23630.78480.042*
H17B0.53090.21450.68390.042*
C180.3751 (4)0.1418 (2)0.7184 (3)0.0395 (9)
H18A0.34170.11780.77800.047*
H18B0.40140.09850.67500.047*
C190.2614 (5)0.1896 (3)0.6683 (3)0.0517 (12)
H19A0.24220.23620.70840.062*
H19B0.29140.20860.60520.062*
C200.1329 (5)0.1419 (3)0.6520 (4)0.0549 (12)
H20A0.06490.17350.61530.082*
H20B0.09790.12730.71460.082*
H20C0.15260.09410.61540.082*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Pt10.03067 (12)0.04558 (14)0.03345 (13)−0.00168 (10)0.00587 (8)−0.00881 (11)
S10.0354 (5)0.0561 (6)0.0392 (6)0.0020 (5)0.0066 (4)−0.0062 (5)
S20.0336 (5)0.0607 (7)0.0379 (5)0.0017 (5)0.0067 (4)−0.0022 (5)
C10.037 (2)0.033 (2)0.040 (2)0.0008 (17)0.0046 (17)−0.0123 (17)
C20.040 (2)0.034 (2)0.045 (2)0.0013 (18)0.0059 (19)−0.0068 (18)
C30.049 (3)0.039 (2)0.043 (2)−0.001 (2)0.009 (2)−0.0047 (19)
C40.053 (3)0.032 (2)0.043 (3)−0.0012 (19)0.014 (2)−0.0088 (19)
N10.045 (2)0.063 (3)0.069 (3)0.001 (2)0.022 (2)0.004 (2)
N20.071 (3)0.047 (2)0.050 (2)0.006 (2)0.008 (2)0.0006 (19)
N30.0361 (17)0.0295 (16)0.0282 (17)0.0022 (13)0.0071 (13)0.0044 (13)
C50.038 (2)0.0298 (19)0.031 (2)0.0043 (16)0.0081 (16)−0.0007 (15)
C60.067 (3)0.047 (3)0.041 (3)0.003 (2)0.024 (2)0.007 (2)
C70.060 (3)0.056 (3)0.045 (3)0.002 (2)0.026 (2)0.000 (2)
C80.080 (4)0.102 (5)0.083 (4)−0.016 (4)0.034 (4)−0.046 (4)
C90.043 (2)0.030 (2)0.037 (2)−0.0031 (17)0.0095 (18)0.0057 (17)
C100.041 (2)0.038 (2)0.043 (2)−0.0033 (18)0.0023 (19)0.0032 (18)
C110.053 (3)0.041 (2)0.043 (2)−0.007 (2)0.000 (2)0.0058 (19)
C120.054 (3)0.057 (3)0.052 (3)−0.011 (2)−0.008 (2)−0.004 (2)
C130.039 (2)0.030 (2)0.028 (2)0.0020 (16)0.0077 (16)0.0059 (15)
C140.053 (3)0.033 (2)0.039 (2)0.0041 (18)0.0141 (19)0.0023 (18)
C150.047 (2)0.042 (2)0.028 (2)0.0022 (19)0.0080 (18)−0.0009 (17)
C160.055 (3)0.055 (3)0.040 (3)0.003 (2)0.016 (2)0.000 (2)
C170.041 (2)0.034 (2)0.032 (2)0.0081 (17)0.0054 (17)0.0061 (16)
C180.042 (2)0.039 (2)0.037 (2)0.0074 (18)0.0019 (18)0.0018 (18)
C190.049 (3)0.055 (3)0.051 (3)0.012 (2)−0.001 (2)0.008 (2)
C200.044 (3)0.068 (3)0.052 (3)0.012 (2)−0.003 (2)0.001 (2)

Geometric parameters (Å, °)

Pt1—S22.3184 (10)C10—H10B0.9900
Pt1—S2i2.3185 (10)C11—C121.504 (6)
Pt1—S12.3310 (11)C11—H11A0.9900
Pt1—S1i2.3310 (11)C11—H11B0.9900
S1—C11.729 (4)C12—H12A0.9800
S2—C11.735 (4)C12—H12B0.9800
C1—C21.361 (6)C12—H12C0.9800
C2—C31.429 (6)C13—C141.519 (5)
C2—C41.430 (6)C13—H13A0.9900
C3—N11.142 (5)C13—H13B0.9900
C4—N21.132 (6)C14—C151.509 (6)
N3—C91.516 (5)C14—H14A0.9900
N3—C51.516 (4)C14—H14B0.9900
N3—C171.518 (5)C15—C161.517 (6)
N3—C131.522 (4)C15—H15A0.9900
C5—C61.522 (5)C15—H15B0.9900
C5—H5A0.9900C16—H16A0.9800
C5—H5B0.9900C16—H16B0.9800
C6—C71.518 (6)C16—H16C0.9800
C6—H6A0.9900C17—C181.508 (6)
C6—H6B0.9900C17—H17A0.9900
C7—C81.480 (8)C17—H17B0.9900
C7—H7A0.9900C18—C191.522 (6)
C7—H7B0.9900C18—H18A0.9900
C8—H8A0.9800C18—H18B0.9900
C8—H8B0.9800C19—C201.511 (7)
C8—H8C0.9800C19—H19A0.9900
C9—C101.521 (6)C19—H19B0.9900
C9—H9A0.9900C20—H20A0.9800
C9—H9B0.9900C20—H20B0.9800
C10—C111.521 (6)C20—H20C0.9800
C10—H10A0.9900
S2—Pt1—S2i180.0C12—C11—H11A108.8
S2—Pt1—S174.35 (4)C10—C11—H11A108.8
S2i—Pt1—S1105.65 (4)C12—C11—H11B108.8
S2—Pt1—S1i105.65 (4)C10—C11—H11B108.8
S2i—Pt1—S1i74.35 (4)H11A—C11—H11B107.7
S1—Pt1—S1i180.0C11—C12—H12A109.5
C1—S1—Pt188.49 (15)C11—C12—H12B109.5
C1—S2—Pt188.74 (14)H12A—C12—H12B109.5
C2—C1—S1126.4 (3)C11—C12—H12C109.5
C2—C1—S2125.2 (3)H12A—C12—H12C109.5
S1—C1—S2108.4 (2)H12B—C12—H12C109.5
C1—C2—C3120.9 (4)C14—C13—N3115.9 (3)
C1—C2—C4121.0 (4)C14—C13—H13A108.3
C3—C2—C4118.1 (4)N3—C13—H13A108.3
N1—C3—C2179.6 (5)C14—C13—H13B108.3
N2—C4—C2178.8 (5)N3—C13—H13B108.3
C9—N3—C5111.7 (3)H13A—C13—H13B107.4
C9—N3—C17106.4 (3)C15—C14—C13110.3 (3)
C5—N3—C17111.2 (3)C15—C14—H14A109.6
C9—N3—C13110.9 (3)C13—C14—H14A109.6
C5—N3—C13105.6 (3)C15—C14—H14B109.6
C17—N3—C13111.2 (3)C13—C14—H14B109.6
N3—C5—C6116.3 (3)H14A—C14—H14B108.1
N3—C5—H5A108.2C14—C15—C16113.5 (4)
C6—C5—H5A108.2C14—C15—H15A108.9
N3—C5—H5B108.2C16—C15—H15A108.9
C6—C5—H5B108.2C14—C15—H15B108.9
H5A—C5—H5B107.4C16—C15—H15B108.9
C7—C6—C5110.5 (4)H15A—C15—H15B107.7
C7—C6—H6A109.5C15—C16—H16A109.5
C5—C6—H6A109.5C15—C16—H16B109.5
C7—C6—H6B109.5H16A—C16—H16B109.5
C5—C6—H6B109.5C15—C16—H16C109.5
H6A—C6—H6B108.1H16A—C16—H16C109.5
C8—C7—C6114.8 (5)H16B—C16—H16C109.5
C8—C7—H7A108.6C18—C17—N3116.2 (3)
C6—C7—H7A108.6C18—C17—H17A108.2
C8—C7—H7B108.6N3—C17—H17A108.2
C6—C7—H7B108.6C18—C17—H17B108.2
H7A—C7—H7B107.5N3—C17—H17B108.2
C7—C8—H8A109.5H17A—C17—H17B107.4
C7—C8—H8B109.5C17—C18—C19112.0 (3)
H8A—C8—H8B109.5C17—C18—H18A109.2
C7—C8—H8C109.5C19—C18—H18A109.2
H8A—C8—H8C109.5C17—C18—H18B109.2
H8B—C8—H8C109.5C19—C18—H18B109.2
N3—C9—C10116.6 (3)H18A—C18—H18B107.9
N3—C9—H9A108.1C20—C19—C18112.2 (4)
C10—C9—H9A108.1C20—C19—H19A109.2
N3—C9—H9B108.1C18—C19—H19A109.2
C10—C9—H9B108.1C20—C19—H19B109.2
H9A—C9—H9B107.3C18—C19—H19B109.2
C11—C10—C9110.5 (3)H19A—C19—H19B107.9
C11—C10—H10A109.6C19—C20—H20A109.5
C9—C10—H10A109.6C19—C20—H20B109.5
C11—C10—H10B109.6H20A—C20—H20B109.5
C9—C10—H10B109.6C19—C20—H20C109.5
H10A—C10—H10B108.1H20A—C20—H20C109.5
C12—C11—C10113.8 (4)H20B—C20—H20C109.5
S2—Pt1—S1—C10.38 (13)C5—C6—C7—C867.3 (6)
S2i—Pt1—S1—C1−179.62 (13)C5—N3—C9—C10−57.1 (4)
S1—Pt1—S2—C1−0.38 (13)C17—N3—C9—C10−178.6 (3)
S1i—Pt1—S2—C1179.62 (13)C13—N3—C9—C1060.4 (4)
Pt1—S1—C1—C2179.1 (4)N3—C9—C10—C11178.2 (3)
Pt1—S1—C1—S2−0.52 (17)C9—C10—C11—C12−177.5 (4)
Pt1—S2—C1—C2−179.1 (3)C9—N3—C13—C1461.4 (4)
Pt1—S2—C1—S10.52 (17)C5—N3—C13—C14−177.5 (3)
S1—C1—C2—C3−175.8 (3)C17—N3—C13—C14−56.8 (4)
S2—C1—C2—C33.8 (6)N3—C13—C14—C15178.8 (3)
S1—C1—C2—C43.9 (6)C13—C14—C15—C16−178.0 (4)
S2—C1—C2—C4−176.6 (3)C9—N3—C17—C18−176.2 (3)
C9—N3—C5—C6−59.8 (4)C5—N3—C17—C1862.0 (4)
C17—N3—C5—C658.9 (4)C13—N3—C17—C18−55.3 (4)
C13—N3—C5—C6179.6 (4)N3—C17—C18—C19178.0 (3)
N3—C5—C6—C7173.5 (4)C17—C18—C19—C20−173.8 (4)

Symmetry codes: (i) −x+1, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: PK2127).

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