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Acta Crystallogr Sect E Struct Rep Online. 2010 October 1; 66(Pt 10): m1300.
Published online 2010 September 25. doi:  10.1107/S1600536810028989
PMCID: PMC2983139

Poly[[hexa­aqua­tris­[μ2-2,5-dihy­droxy-1,4-benzoquinona­to(2−)]diholmium(III)] octa­deca­hydrate]

Abstract

In the polymeric title compound, {[Ho2(C6H2O4)3(H2O)6]·18H2O}n, the HoIII ion is nine-coordinated by six O atoms derived from three bidentate 2,5-dihy­droxy-1,4-benzoquinonate (DHBQ2−) ligands and three O atoms from three water mol­ecules. The HoIII ions are connected via three ligands, resulting in the formation of a two-dimensional honeycomb layer parallel to the ab plane. The layer is racemic in which Δ- and Λ-coordination geometries around HoIII ions are alternately arranged. The asymmetric unit comprises a third of a HoIII ion, located on a threefold axis, one-half of a DHBQ2− ion, located on a centre of inversion, one coordinated water mol­ecule and three uncoordinated water mol­ecules.

Related literature

For general background, see: Kitagawa & Kawata (2002 [triangle]); Nakabayashi & Ohkoshi (2009 [triangle]); Ohkoshi et al. (2001 [triangle]). For details of the synthesis, see: Weider et al. (1985 [triangle]). For related structures, see: Robl & Sheldrick (1988 [triangle]); Weiss et al. (1986 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-m1300-scheme1.jpg

Experimental

Crystal data

  • [Ho2(C6H2O4)3(H2O)6]·18H2O
  • M r = 1176.46
  • Trigonal, An external file that holds a picture, illustration, etc.
Object name is e-66-m1300-efi1.jpg
  • a = 14.1407 (3) Å
  • c = 18.0629 (5) Å
  • V = 3127.93 (12) Å3
  • Z = 3
  • Mo Kα radiation
  • μ = 3.88 mm−1
  • T = 90 K
  • 0.10 × 0.10 × 0.04 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995 [triangle]) T min = 0.704, T max = 0.856
  • 11262 measured reflections
  • 1594 independent reflections
  • 1525 reflections with I > 2σ(I)
  • R int = 0.025

Refinement

  • R[F 2 > 2σ(F 2)] = 0.023
  • wR(F 2) = 0.063
  • S = 1.23
  • 1594 reflections
  • 86 parameters
  • H-atom parameters constrained
  • Δρmax = 0.65 e Å−3
  • Δρmin = −0.30 e Å−3

Data collection: PROCESS-AUTO (Rigaku, 1998 [triangle]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and pyMOL (DeLano, 2007 [triangle]); software used to prepare material for publication: CrystalStructure.

Table 1
Selected bond lengths (Å)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810028989/tk2691sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810028989/tk2691Isup2.hkl

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

Acknowledgments

We are thankful for a Grant-in-Aid for Young Scientists (S) from JSPS, the Global COE Program, "Chemistry Innovation through Cooperation of Science and Engineering" from MEXT Japan, the Photon Frontier Network Program from MEXT, the Izumi Science and Technology Foundation and Asahi Glass Foundation. We also thank the Cryogenic Research Center and the Center for Nano Lithography & Analysis, The University of Tokyo, supported by MEXT Japan. This work has been approved by the Photon Factory Program Advisory Committee (Proposal 2009 G678).

supplementary crystallographic information

Comment

Lanthanide complexes have attracted attention as magnetic and luminescent materials due to the properties of the 4f orbitals in lanthanide ions. Although the magnetism of mononuclear lanthanide complexes are well understood, studies on polynuclear lanthanide complexes are much less advanced (Ohkoshi et al., 2001). The dimensionality of complexes and coordination geometry around lanthanide ions are key factors to control their magnetic properties. From this viewpoint, constructing polynuclear lanthanide complexes with various topologies are interesting. In our previous work, we reported the 3-D monometallic lanthanide metal assembly, Na5[{Ho(THB4-)2}.7H2O]n (THB = 1,2,4,5-tetrahydroxybenzene) (Nakabayashi et al., 2009). In this work, we synthesized a 2-D honeycomb network composed of holmium ions (HoIII) and 2,5-dihydroxy-1,4-benzoquinonate, [{Ho2 (DHBQ2-)3 (H2O)6}.18H2O]n (Kitagawa et al., 2002; Robl et al., 1988).

The asymmetric unit comprises a third of a HoIII ion, being located on a three-fold axis, one-half of a DHBQ2- ion, being disposed about a centre of inversion, one coordinated water molecule, and three zeolitic water molecules.

The C—O distances of 1.276 (4) Å (C1—O1) and 1.274 (3) Å (C2—O2) in this compound agree with those of the DHBQ2- ligands which were previously reported, e.g. 1.276 (6) Å (Weiss et al. 1986). In the coordination geometry, a HoIII ion is coordinated to six O atoms from three bidentate DHBQ2- ligands and three O atoms from three water molecules (Fig. 1 and Table 1). The HoIII ion is connected via three ligands, which results in a two-dimensional honeycomb layer with a diameter of 16.6 Å. The layer has a racemic structure in which Δ- and Λ-coordination geometries around HoIII ions are alternately arranged (Fig. 2). The zeolitic water molecules occupy regions between the layers.

The product of the molar magnetic susceptibility (χM) and temperature (T), χMT, values at room temperature was 13.6 cm3 K mol-1. This value nearly corresponds to the expected value of 13.9 cm3 K mol-1 due to HoIII ions (J = 8, L = 6, S = 2, and g = 5/4).

All known compounds of this type have two specific structures, honeycomb or racemic, and show paramagnetism. Mixing lanthanide ions, the chiral lanthanide assemblies with Δ- or Λ-coordination geometries are targeted for synthesis, which should show a magneto-chiral dichroism. A study to clarify this hypotheses, work is currently under way.

Experimental

Under air, aqueous solutions of 0.1 M Ho(NO3)3 and 0.4 M 1,2,4,5-tetrahydroxybenzene (THB) (Weider et al., 1985) mixed. THB was gradually oxidized to 2,5-dihydroxy-1,4-benzoquinone (DHBQ) in the mixed solution, and slow complexation of Ho(NO3)3 and DHBQ) produced red crystals of the title polymer in 24% yield within a week. The obtained polycrystalline compound was dried under air. Elemental analysis indicated the formula was [Ho2(C6H2O4)3(H2O)6].17H2O, C18H52O35Ho2, calcd. Ho, 28.18%; C, 18.47%; H, 4.49%, found. Ho, 28.29%; C, 18.23%; H, 4.64%. There is a slight difference of zeolitic water molecules between the elemental analysis and the crystallographic formulation because zeolitic water molecules are easy to be lost from the crystals and their number depends on the drying processes.

Refinement

The H atoms were placed in their calculated positions,with C—H = 0.95 Å, and refined using a riding model, with Uiso(H) = 1.2 Ueq(C).

Figures

Fig. 1.
A part of the title polymeric compound, thermal ellipsoids are shown at the 50% probability level. Blue, gray, and red represent Ho, C and O atoms, respectively. The labeled atoms indicate all independent atoms.
Fig. 2.
A layer with a honeycomb structure. Blue spheres and gray sticks represent Ho atoms and other atoms (C and O), respectively.

Crystal data

[Ho2(C6H2O4)3(H2O)6]·18H2ODx = 1.796 Mg m3
Mr = 1176.46Mo Kα radiation, λ = 0.71075 Å
Trigonal, R3Cell parameters from 9640 reflections
Hall symbol: -R 3θ = 3.4–27.5°
a = 14.1407 (3) ŵ = 3.88 mm1
c = 18.0629 (5) ÅT = 90 K
V = 3127.93 (12) Å3Platelet, red
Z = 30.10 × 0.10 × 0.04 mm
F(000) = 1608.00

Data collection

Rigaku R-AXIS RAPID diffractometer1525 reflections with F2 > 2σ(F2)
Detector resolution: 10.00 pixels mm-1Rint = 0.025
ω scansθmax = 27.5°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)h = −18→18
Tmin = 0.704, Tmax = 0.856k = −18→18
11262 measured reflectionsl = −23→23
1594 independent reflections

Refinement

Refinement on F2H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.023w = 1/[σ2(Fo2) + (0.0248P)2 + 19.995P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.063(Δ/σ)max = 0.002
S = 1.23Δρmax = 0.65 e Å3
1594 reflectionsΔρmin = −0.30 e Å3
86 parameters

Special details

Geometry. loop_ _Bond lengths and angles Ho1 - Distance Angles O1_$1 2.3715 (0.0023) O1 2.3715 (0.0024) 78.04 (0.09) O1_$2 2.3715 (0.0023) 78.05 (0.09) 78.05 (0.09) O3_$2 2.3851 (0.0025) 138.54 (0.09) 85.02 (0.10) 134.88 (0.09) O3_$1 2.3851 (0.0025) 134.88 (0.09) 138.54 (0.09) 85.02 (0.10) 80.68 (0.11) O3 2.3852 (0.0025) 85.02 (0.10) 134.88 (0.09) 138.54 (0.09) 80.68 (0.11) 80.68 (0.11) O2_$1 2.4626 (0.0024) 65.01 (0.08) 134.82 (0.08) 69.90 (0.08) 140.07 (0.09) 69.92 (0.09) 68.65 (0.09) O2 2.4626 (0.0023) 69.90 (0.08) 65.01 (0.08) 134.82 (0.08) 68.65 (0.09) 140.07 (0.09) 69.92 (0.08) 119.91 (0.01) O2_$2 2.4626 (0.0023) 134.82 (0.08) 69.90 (0.08) 65.01 (0.08) 69.92 (0.08) 68.65 (0.09) 140.07 (0.09) 119.91 (0.01) Ho1 - O1_$1 O1 O1_$2 O3_$2 O3_$1 O3 O2_$1 O1 - Distance Angles C1 1.2764 (0.0041) Ho1 2.3715 (0.0023) 123.38 (0.21) O1 - C1 O2 - Distance Angles C2 1.2739 (0.0041) Ho1 2.4626 (0.0023) 119.92 (0.21) O2 - C2 O3 - Distance Angles Ho1 2.3852 (0.0025) O3 - C1 - Distance Angles O1 1.2764 (0.0041) C3 1.3846 (0.0049) 125.21 (0.32) C2 1.5290 (0.0046) 114.26 (0.29) 120.50 (0.30) C1 - O1 C3 C3 - Distance Angles C1 1.3846 (0.0049) C2_$3 1.3982 (0.0048) 119.67 (0.32) H3 0.9500 120.16 120.16 C3 - C1 C2_$3 C2 - Distance Angles O2 1.2739 (0.0041) C3_$3 1.3982 (0.0048) 124.89 (0.31) C1 1.5290 (0.0046) 115.30 (0.29) 119.80 (0.30) C2 - O2 C3_$3
Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt).

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

xyzUiso*/Ueq
Ho10.00000.00000.754297 (13)0.01802 (8)
O1−0.1198 (2)−0.12391 (19)0.66415 (13)0.0270 (5)
O2−0.00678 (19)−0.17736 (19)0.75023 (13)0.0252 (4)
O30.1248 (2)−0.0026 (2)0.84201 (15)0.0366 (6)
O40.1390 (2)−0.1541 (2)0.93023 (18)0.0481 (7)
O50.2672 (2)0.1817 (2)0.92192 (19)0.0508 (7)
O6−0.1882 (2)−0.0598 (2)0.54192 (17)0.0474 (7)
C1−0.1492 (2)−0.2252 (2)0.66312 (19)0.0246 (6)
C3−0.2332 (2)−0.3039 (2)0.6206 (2)0.0283 (7)
C2−0.0802 (2)−0.2555 (2)0.71218 (18)0.0237 (6)
H3−0.2770−0.28500.59120.034*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Ho10.01630 (11)0.01630 (11)0.02146 (14)0.00815 (5)0.00000.0000
O10.0310 (13)0.0178 (11)0.0320 (12)0.0121 (10)−0.0067 (9)−0.0020 (9)
O20.0240 (11)0.0194 (11)0.0316 (12)0.0103 (9)−0.0047 (9)−0.0032 (9)
O30.0363 (14)0.0309 (14)0.0405 (14)0.0154 (12)−0.0164 (11)−0.0020 (11)
O40.0455 (18)0.0513 (18)0.0552 (18)0.0299 (15)−0.0062 (14)0.0051 (15)
O50.0490 (18)0.0453 (18)0.0558 (19)0.0218 (15)−0.0121 (15)−0.0078 (14)
O60.0528 (19)0.0470 (18)0.0418 (16)0.0244 (15)−0.0105 (13)0.0015 (13)
C10.0241 (16)0.0227 (15)0.0271 (15)0.0116 (13)0.0016 (12)0.0014 (12)
C30.0274 (17)0.0235 (17)0.0334 (17)0.0122 (14)−0.0049 (13)0.0001 (13)
C20.0228 (15)0.0236 (16)0.0241 (15)0.0111 (13)0.0019 (12)0.0005 (12)

Geometric parameters (Å, °)

Ho1—O12.371 (2)Ho1—O3ii2.385 (2)
Ho1—O1i2.371 (2)O1—C11.276 (4)
Ho1—O1ii2.371 (2)O2—C21.274 (3)
Ho1—O22.463 (2)C1—C31.385 (4)
Ho1—O2i2.4625 (19)C1—C21.529 (6)
Ho1—O2ii2.463 (3)C3—C2iii1.398 (5)
Ho1—O32.385 (3)C3—H30.950
Ho1—O3i2.385 (3)
Ho1···C13.253 (3)O6···C13.444 (5)
Ho1···C1i3.253 (3)O6···C1ii3.369 (4)
Ho1···C1ii3.253 (4)O6···C33.485 (5)
Ho1···C23.289 (3)O6···C3xi3.326 (5)
Ho1···C2i3.289 (2)C1···Ho13.253 (3)
Ho1···C2ii3.289 (4)C1···O1i3.592 (3)
O1···O1i2.986 (3)C1···O22.372 (4)
O1···O1ii2.986 (3)C1···O3ii3.481 (4)
O1···O22.599 (4)C1···O63.444 (5)
O1···O2ii2.770 (4)C1···O6i3.369 (4)
O1···O3ii3.214 (3)C1···C1iii2.847 (5)
O1···O4iv3.464 (4)C1···C3iii2.533 (6)
O1···O62.740 (4)C1···C2iii2.406 (4)
O1···O6i3.390 (4)C3···O12.363 (3)
O1···C1ii3.592 (5)C3···O2iii2.370 (4)
O1···C32.363 (3)C3···O63.485 (5)
O1···C22.360 (5)C3···O6xii3.326 (4)
O1···C2ii3.458 (5)C3···C1iii2.533 (6)
O2···O12.599 (4)C3···C3iii2.927 (6)
O2···O1i2.770 (3)C3···C22.531 (5)
O2···O32.778 (3)C2···Ho13.289 (3)
O2···O3ii2.734 (4)C2···O12.360 (5)
O2···O4v2.868 (5)C2···O1i3.458 (3)
O2···O5ii3.325 (4)C2···O3ii3.254 (5)
O2···C12.372 (4)C2···O4v3.499 (5)
O2···C3iii2.370 (4)C2···C1iii2.406 (4)
O3···O1i3.214 (3)C2···C32.531 (5)
O3···O22.778 (3)C2···C2iii2.855 (4)
O3···O2i2.734 (3)O1···H32.608
O3···O3i3.088 (5)O2···H3iii2.614
O3···O3ii3.088 (4)O4···H3ix3.259
O3···O42.757 (5)O4···H3vi3.484
O3···O52.772 (3)O5···H3ix3.135
O3···C1i3.481 (4)O6···H32.918
O3···C2i3.254 (3)O6···H3xi3.032
O4···O1vi3.464 (5)C1···H32.035
O4···O2v2.868 (5)C1···H3iii3.400
O4···O32.757 (5)C2···H33.396
O4···O5ii2.753 (4)C2···H3iii2.048
O4···O5vii2.802 (4)H3···O12.608
O4···C2v3.499 (5)H3···O2iii2.614
O5···O2i3.325 (4)H3···O4x3.259
O5···O32.772 (3)H3···O4iv3.484
O5···O4i2.753 (6)H3···O5x3.135
O5···O4viii2.802 (4)H3···O62.918
O5···O6ix2.728 (4)H3···O6xii3.032
O6···O12.740 (4)H3···C12.035
O6···O1ii3.390 (3)H3···C1iii3.400
O6···O5x2.728 (4)H3···C23.396
O6···O6xi2.801 (4)H3···C2iii2.048
O6···O6xii2.801 (5)
O1—Ho1—O1i78.04 (8)O2—Ho1—O3i140.07 (9)
O1—Ho1—O1ii78.04 (8)O2—Ho1—O3ii68.65 (10)
O1—Ho1—O265.01 (9)O2i—Ho1—O2ii119.91 (9)
O1—Ho1—O2i134.81 (7)O2i—Ho1—O368.65 (8)
O1—Ho1—O2ii69.90 (9)O2i—Ho1—O3i69.92 (8)
O1—Ho1—O3134.88 (10)O2i—Ho1—O3ii140.07 (8)
O1—Ho1—O3i138.54 (11)O2ii—Ho1—O3140.07 (9)
O1—Ho1—O3ii85.02 (8)O2ii—Ho1—O3i68.65 (9)
O1i—Ho1—O1ii78.04 (10)O2ii—Ho1—O3ii69.92 (10)
O1i—Ho1—O269.90 (8)O3—Ho1—O3i80.68 (11)
O1i—Ho1—O2i65.01 (8)O3—Ho1—O3ii80.68 (9)
O1i—Ho1—O2ii134.81 (8)O3i—Ho1—O3ii80.68 (9)
O1i—Ho1—O385.02 (10)Ho1—O1—C1123.4 (2)
O1i—Ho1—O3i134.88 (7)Ho1—O2—C2119.9 (2)
O1i—Ho1—O3ii138.54 (10)O1—C1—C3125.2 (4)
O1ii—Ho1—O2134.81 (8)O1—C1—C2114.3 (2)
O1ii—Ho1—O2i69.90 (8)C3—C1—C2120.5 (3)
O1ii—Ho1—O2ii65.01 (8)C1—C3—C2iii119.7 (4)
O1ii—Ho1—O3138.54 (7)O2—C2—C1115.3 (3)
O1ii—Ho1—O3i85.02 (9)O2—C2—C3iii124.9 (3)
O1ii—Ho1—O3ii134.88 (11)C1—C2—C3iii119.8 (2)
O2—Ho1—O2i119.91 (9)C1—C3—H3120.2
O2—Ho1—O2ii119.91 (7)C2iii—C3—H3120.2
O2—Ho1—O369.92 (9)
O1—Ho1—O1i—C1i166.8 (3)O3—Ho1—O1ii—C1ii−125.1 (2)
O1i—Ho1—O1—C186.7 (2)O3i—Ho1—O1ii—C1ii−55.3 (2)
O1—Ho1—O1ii—C1ii86.7 (2)O3ii—Ho1—O1ii—C1ii16.3 (2)
O1ii—Ho1—O1—C1166.8 (2)O2—Ho1—O2i—C2i34.3 (2)
O1—Ho1—O2—C2−10.8 (2)O2i—Ho1—O2—C2−139.8 (2)
O2—Ho1—O1—C113.5 (2)O2—Ho1—O2ii—C2ii−139.8 (2)
O1—Ho1—O2i—C2i−49.0 (3)O2ii—Ho1—O2—C234.3 (2)
O2i—Ho1—O1—C1121.7 (2)O3—Ho1—O2—C2171.3 (2)
O1—Ho1—O2ii—C2ii−96.6 (2)O3i—Ho1—O2—C2126.2 (2)
O2ii—Ho1—O1—C1−125.7 (2)O3ii—Ho1—O2—C283.8 (2)
O3—Ho1—O1—C116.3 (3)O2i—Ho1—O2ii—C2ii34.3 (2)
O3i—Ho1—O1—C1−125.1 (2)O2ii—Ho1—O2i—C2i−139.8 (2)
O3ii—Ho1—O1—C1−55.3 (2)O3—Ho1—O2i—C2i83.8 (2)
O1i—Ho1—O1ii—C1ii166.8 (2)O3i—Ho1—O2i—C2i171.3 (2)
O1ii—Ho1—O1i—C1i86.7 (3)O3ii—Ho1—O2i—C2i126.2 (2)
O1i—Ho1—O2—C2−96.6 (2)O3—Ho1—O2ii—C2ii126.2 (2)
O2—Ho1—O1i—C1i−125.7 (3)O3i—Ho1—O2ii—C2ii83.8 (2)
O1i—Ho1—O2i—C2i−10.8 (2)O3ii—Ho1—O2ii—C2ii171.3 (2)
O2i—Ho1—O1i—C1i13.5 (3)Ho1—O1—C1—C3167.6 (2)
O1i—Ho1—O2ii—C2ii−49.0 (2)Ho1—O1—C1—C2−14.4 (4)
O2ii—Ho1—O1i—C1i121.7 (3)Ho1—O2—C2—C18.1 (3)
O3—Ho1—O1i—C1i−55.3 (3)Ho1—O2—C2—C3iii−171.9 (2)
O3i—Ho1—O1i—C1i16.3 (3)O1—C1—C3—C2iii176.2 (3)
O3ii—Ho1—O1i—C1i−125.1 (3)O1—C1—C2—O23.4 (4)
O1ii—Ho1—O2—C2−49.0 (2)O1—C1—C2—C3iii−176.5 (3)
O2—Ho1—O1ii—C1ii121.7 (2)C3—C1—C2—O2−178.4 (3)
O1ii—Ho1—O2i—C2i−96.6 (2)C3—C1—C2—C3iii1.7 (5)
O2i—Ho1—O1ii—C1ii−125.7 (2)C2—C1—C3—C2iii−1.7 (5)
O1ii—Ho1—O2ii—C2ii−10.8 (2)C1—C3—C2iii—O2iii−178.5 (3)
O2ii—Ho1—O1ii—C1ii13.5 (2)C1—C3—C2iii—C1iii1.6 (5)

Symmetry codes: (i) −y, xy, z; (ii) −x+y, −x, z; (iii) −x−1/3, −y−2/3, −z+4/3; (iv) xy−2/3, x−1/3, −z+5/3; (v) −x+1/3, −y−1/3, −z+5/3; (vi) y+1/3, −x+y−1/3, −z+5/3; (vii) y, −x+y, −z+2; (viii) xy, x, −z+2; (ix) x+2/3, y+1/3, z+1/3; (x) x−2/3, y−1/3, z−1/3; (xi) y, −x+y, −z+1; (xii) xy, x, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2691).

References

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