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ISSN: 2056-9890

Piperazine-1,4-diium bis­­(2-carb­­oxy-1H-pyrazole-4-carboxyl­ate) tetra­hydrate

aKey Laboratory for Organic Electronics & Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications (NUPT), Nanjing 210046, People's Republic of China
*Correspondence e-mail: iamxhzhou@njupt.edu.cn

(Received 8 September 2010; accepted 13 September 2010; online 18 September 2010)

The asymmetric unit of the title compound, C4H12N22+·2C5H3N2O4·4H2O, comprises one-half of a piperazine-1,4-diium cation, which lies on an inversion centre, a 2-carb­oxy-1H-pyrazole-4-carboxyl­ate anion and two water mol­ecules. An extensive network of inter­molecular O—H⋯O, N—H⋯O, N—H⋯N and C—H⋯O hydrogen bonds between the cations, anions and water mol­ecules leads to a three-dimensional supra­molecular framework.

Related literature

For 3,5-pyrazole­dicarb­oxy­lic acid, see: King et al. (2003[King, P., Clèrac, R., Anson, C. E., Coulon, C. & Powell, A. K. (2003). Inorg. Chem. 42, 3492-3500.]); Pan et al. (2001[Pan, L., Ching, N., Huang, X. Y. & Li, J. (2001). Chem. Eur. J. 7, 4431-4437.]). For reference structural data, see: Li & Su (2007[Li, Z.-H. & Su, K.-M. (2007). Acta Cryst. E63, o4744.]); Reviriego et al. (2006[Reviriego, F., Rodriguez-Franco, M. I., Navarro, P., Garcĺa-España, E., Liu-González, M., Verdejo, B. & Domènech, A. (2006). J. Am. Chem. Soc. 128, 16458-16459.]).

[Scheme 1]

Experimental

Crystal data
  • C4H12N2·2C5H3N2O4·4H2O

  • Mr = 470.41

  • Monoclinic, P 21 /c

  • a = 8.3363 (13) Å

  • b = 16.246 (3) Å

  • c = 7.3930 (11) Å

  • β = 90.812 (3)°

  • V = 1001.2 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.14 mm−1

  • T = 291 K

  • 0.15 × 0.14 × 0.12 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SMART, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.980, Tmax = 0.984

  • 5265 measured reflections

  • 1946 independent reflections

  • 1524 reflections with I > 2σ(I)

  • Rint = 0.051

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.147

  • S = 1.10

  • 1946 reflections

  • 169 parameters

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

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O5i 0.84 (3) 1.93 (3) 2.746 (3) 167 (3)
O2—H2⋯O4ii 0.87 (3) 1.65 (3) 2.520 (2) 175 (3)
N3—H3A⋯O4 0.88 (3) 2.36 (3) 2.918 (3) 121 (2)
N3—H3A⋯N2 0.88 (3) 2.01 (3) 2.865 (3) 162 (3)
N3—H3B⋯O3iii 0.88 (3) 2.20 (3) 2.999 (3) 150 (3)
O5—H5B⋯O6 0.85 (4) 2.00 (4) 2.831 (3) 166 (3)
O5—H5A⋯O6iv 0.92 (4) 1.96 (4) 2.833 (3) 157 (3)
O6—H6C⋯O3v 0.93 (3) 1.85 (3) 2.779 (3) 173 (3)
O6—H6D⋯O3vi 0.76 (3) 2.14 (3) 2.858 (3) 158 (4)
C6—H6B⋯O5vii 0.97 2.53 3.348 (4) 142
C7—H7A⋯O1viii 0.97 2.53 3.091 (3) 117
Symmetry codes: (i) x+1, y, z; (ii) [x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (iv) -x, -y+1, -z+1; (v) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (vi) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (vii) -x+1, -y+1, -z; (viii) [x-1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART, SADABS and SAINT. Bruker 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: DIAMOND (Brandenburg, 2008[Brandenburg, K. (2008). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Hydrogen bonding, as the strongest and most directional intermolecular force, has been intensively investigated in organic crystalline solids. The ligand, 3,5-pyrazoledicarboxylic acid, known both as a multiple proton donor and acceptor, has six potential hydrogen-bond sites involving both the nitrogen atoms of the pyrazole ring and all of the carboxylate O atoms. and it can form mono-, di- and trianionic ligand species through deprotonation (King et al. 2003; Pan et al. 2001).

We report here the synthesis and structure of piperazine-1,4-diium bis(2-carboxy-1H-pyrazole-4-carboxylate) tetrahydrate, as shown in Fig.1, which was obtained from a solution of 3,5-pyrazoledicarboxylic acid, Cd(NO3)2.4H2O and piperazine. Bond distances and angles are normal (Li & Su, 2007; Reviriego et al. 2006). The asymmetric unit of the title compound comprises one half of the piperazine-1,4-diium cation, which lies about an inversion centre, a 2-carboxy-1H-pyrazole-4-carboxylate anion and two water molecules. In the crystal structure molecules are interlinked by hydrogen bonds (Table 1 and Fig. 2). The 2-carboxy-1H-pyrazole-4-carboxylate anoins are interconnected with each other through the O2—H2···O4iii hydrogen bonds. The 2-carboxy-1H-pyrazole-4-carboxylate anions are connected with the piperazine-1,4-diium cations through the N3—H3A···O4, N3—H3A···N2, N3—H3B···O3iv and C7—H7A···O1viii hydrogen bonds to form the three-dimensional supramolecular framework.

Related literature top

For 3,5-pyrazoledicarboxylic acid, see: King et al. (2003); Pan et al. (2001). For reference structural data, see: Li & Su (2007); Reviriego et al. (2006).

Experimental top

A mixture of 3,5-pyrazoledicarboxylic acid (0.2 mmol, 34.8 mg), Cd(NO3)2.4H2O (0.1 mmol, 30.8 mg), piperazine (0.2 mmol, 17.2 mg) and H2O (8 ml) was sealed in a 15 ml Teflon-lined bomb and heated at 150°C for 5 days. The reaction mixture was slowly cooled to room temperature to obtain the colorless block crystals of (I) suitable for X-ray diffraction analysis.

Refinement top

Hydrogen atoms bonded to the carbon atoms were placed in calculated positions and refined as riding mode, with C—H = 0.93 Å for aromatic H atom, 0.97 Å for methylene H atoms, respectively, and Uiso(H) = 1.2Ueq(C). The H atoms on the O and N atoms were located in difference Fourier map with their bond lengths freely refined and Uiso(H) = 1.2Ueq(O or N).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with 30% probability displacement ellipsoids. H atoms are shown as small spheres of arbitary radii. [Symmetry code; (i) 1 - x, 1 - y, -z.]
[Figure 2] Fig. 2. A view of the crystal packing. Hydrogen bonds are indicated by green dashed lines.
Piperazine-1,4-diium bis(2-carboxy-1H-pyrazole-4-carboxylate) tetrahydrate top
Crystal data top
C4H12N2·2C5H3N2O4·4H2OF(000) = 496
Mr = 470.41Dx = 1.560 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1373 reflections
a = 8.3363 (13) Åθ = 2.7–24.0°
b = 16.246 (3) ŵ = 0.14 mm1
c = 7.3930 (11) ÅT = 291 K
β = 90.812 (3)°Block, white
V = 1001.2 (3) Å30.15 × 0.14 × 0.12 mm
Z = 2
Data collection top
Bruker SMART APEX CCD
diffractometer
1946 independent reflections
Radiation source: fine-focus sealed tube1524 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.051
phi and ω scansθmax = 26.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1010
Tmin = 0.980, Tmax = 0.984k = 1319
5265 measured reflectionsl = 89
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.10 w = 1/[σ2(Fo2) + (0.0729P)2]
where P = (Fo2 + 2Fc2)/3
1946 reflections(Δ/σ)max < 0.001
169 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C4H12N2·2C5H3N2O4·4H2OV = 1001.2 (3) Å3
Mr = 470.41Z = 2
Monoclinic, P21/cMo Kα radiation
a = 8.3363 (13) ŵ = 0.14 mm1
b = 16.246 (3) ÅT = 291 K
c = 7.3930 (11) Å0.15 × 0.14 × 0.12 mm
β = 90.812 (3)°
Data collection top
Bruker SMART APEX CCD
diffractometer
1946 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
1524 reflections with I > 2σ(I)
Tmin = 0.980, Tmax = 0.984Rint = 0.051
5265 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.41 e Å3
1946 reflectionsΔρmin = 0.23 e Å3
169 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
C11.1506 (3)0.78226 (15)0.2962 (3)0.0267 (6)
C20.9861 (3)0.77149 (14)0.2216 (3)0.0233 (6)
C30.8727 (3)0.82885 (15)0.1741 (3)0.0256 (6)
H30.88270.88580.17850.031*
C40.7391 (3)0.78344 (14)0.1178 (3)0.0226 (5)
C50.5785 (3)0.81182 (15)0.0528 (3)0.0246 (6)
C60.6653 (4)0.51108 (17)0.0379 (5)0.0455 (8)
H6A0.71490.49990.07900.055*
H6B0.74960.52420.12230.055*
C70.4237 (3)0.56416 (16)0.1024 (4)0.0380 (7)
H7A0.35090.61070.10700.046*
H7B0.46660.55480.22330.046*
N10.9196 (2)0.69726 (13)0.1933 (3)0.0266 (5)
H10.962 (3)0.6522 (18)0.220 (4)0.032*
N20.7696 (2)0.70254 (12)0.1296 (3)0.0262 (5)
N30.5556 (3)0.58226 (14)0.0224 (3)0.0399 (7)
H3A0.604 (4)0.6268 (19)0.020 (4)0.048*
H3B0.514 (4)0.5944 (18)0.130 (4)0.048*
O11.2097 (2)0.85001 (11)0.3144 (3)0.0454 (6)
O21.2193 (2)0.71272 (11)0.3390 (3)0.0360 (5)
H21.311 (4)0.7215 (17)0.394 (4)0.043*
O30.5431 (2)0.88609 (10)0.0779 (3)0.0360 (5)
O40.4901 (2)0.75870 (11)0.0188 (3)0.0358 (5)
O50.0107 (3)0.53912 (14)0.2765 (4)0.0528 (7)
H5A0.077 (5)0.510 (2)0.316 (5)0.063*
H5B0.093 (5)0.539 (2)0.346 (5)0.063*
O60.2621 (2)0.51492 (13)0.5325 (3)0.0476 (6)
H6C0.323 (4)0.472 (2)0.486 (5)0.057*
H6D0.320 (4)0.549 (2)0.556 (5)0.057*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0215 (13)0.0285 (14)0.0299 (15)0.0002 (11)0.0059 (11)0.0006 (11)
C20.0199 (12)0.0226 (13)0.0272 (14)0.0006 (10)0.0039 (10)0.0002 (10)
C30.0205 (13)0.0193 (12)0.0369 (15)0.0020 (9)0.0056 (10)0.0016 (10)
C40.0189 (12)0.0203 (12)0.0286 (14)0.0011 (10)0.0045 (10)0.0004 (10)
C50.0159 (12)0.0228 (13)0.0351 (15)0.0025 (10)0.0040 (10)0.0030 (11)
C60.0399 (17)0.0443 (18)0.052 (2)0.0078 (14)0.0024 (14)0.0050 (15)
C70.0455 (17)0.0286 (15)0.0398 (17)0.0027 (12)0.0021 (14)0.0035 (12)
N10.0191 (11)0.0186 (11)0.0417 (14)0.0025 (9)0.0092 (9)0.0022 (9)
N20.0169 (10)0.0215 (11)0.0398 (13)0.0001 (8)0.0103 (9)0.0011 (9)
N30.0616 (17)0.0210 (12)0.0370 (15)0.0144 (11)0.0069 (12)0.0007 (10)
O10.0326 (11)0.0284 (11)0.0745 (16)0.0083 (8)0.0248 (10)0.0010 (10)
O20.0195 (9)0.0284 (10)0.0597 (14)0.0004 (8)0.0183 (9)0.0030 (9)
O30.0239 (10)0.0218 (10)0.0622 (14)0.0044 (8)0.0093 (9)0.0002 (9)
O40.0221 (9)0.0282 (10)0.0566 (13)0.0002 (8)0.0167 (9)0.0048 (9)
O50.0395 (12)0.0361 (12)0.0826 (19)0.0042 (10)0.0040 (12)0.0144 (11)
O60.0345 (12)0.0334 (12)0.0748 (17)0.0035 (9)0.0015 (11)0.0107 (11)
Geometric parameters (Å, º) top
C1—O11.213 (3)C6—H6B0.9700
C1—O21.304 (3)C7—N31.476 (4)
C1—C21.481 (3)C7—C6i1.504 (4)
C2—N11.342 (3)C7—H7A0.9700
C2—C31.369 (3)C7—H7B0.9700
C3—C41.395 (3)N1—N21.333 (3)
C3—H30.9300N1—H10.84 (3)
C4—N21.341 (3)N3—H3A0.88 (3)
C4—C51.489 (3)N3—H3B0.88 (3)
C5—O41.248 (3)O2—H20.87 (3)
C5—O31.256 (3)O5—H5A0.92 (4)
C6—N31.480 (4)O5—H5B0.85 (4)
C6—C7i1.504 (4)O6—H6C0.93 (3)
C6—H6A0.9700O6—H6D0.76 (3)
O1—C1—O2125.7 (2)H6A—C6—H6B108.0
O1—C1—C2121.4 (2)N3—C7—C6i109.4 (2)
O2—C1—C2112.9 (2)N3—C7—H7A109.8
N1—C2—C3106.9 (2)C6i—C7—H7A109.8
N1—C2—C1122.8 (2)N3—C7—H7B109.8
C3—C2—C1130.3 (2)C6i—C7—H7B109.8
C2—C3—C4105.2 (2)H7A—C7—H7B108.2
C2—C3—H3127.4N2—N1—C2112.3 (2)
C4—C3—H3127.4N2—N1—H1122.4 (18)
N2—C4—C3110.4 (2)C2—N1—H1125.1 (19)
N2—C4—C5119.6 (2)N1—N2—C4105.21 (19)
C3—C4—C5130.0 (2)C7—N3—C6111.1 (2)
O4—C5—O3126.1 (2)C7—N3—H3A106 (2)
O4—C5—C4116.5 (2)C6—N3—H3A113 (2)
O3—C5—C4117.5 (2)C7—N3—H3B108 (2)
N3—C6—C7i111.0 (2)C6—N3—H3B110 (2)
N3—C6—H6A109.4H3A—N3—H3B108 (3)
C7i—C6—H6A109.4C1—O2—H2110.5 (18)
N3—C6—H6B109.4H5A—O5—H5B117 (3)
C7i—C6—H6B109.4H6C—O6—H6D107 (3)
Symmetry code: (i) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O5ii0.84 (3)1.93 (3)2.746 (3)167 (3)
O2—H2···O4iii0.87 (3)1.65 (3)2.520 (2)175 (3)
N3—H3A···O40.88 (3)2.36 (3)2.918 (3)121 (2)
N3—H3A···N20.88 (3)2.01 (3)2.865 (3)162 (3)
N3—H3B···O3iv0.88 (3)2.20 (3)2.999 (3)150 (3)
O5—H5B···O60.85 (4)2.00 (4)2.831 (3)166 (3)
O5—H5A···O6v0.92 (4)1.96 (4)2.833 (3)157 (3)
O6—H6C···O3vi0.93 (3)1.85 (3)2.779 (3)173 (3)
O6—H6D···O3vii0.76 (3)2.14 (3)2.858 (3)158 (4)
C6—H6B···O5i0.972.533.348 (4)142
C7—H7A···O1viii0.972.533.091 (3)117
Symmetry codes: (i) x+1, y+1, z; (ii) x+1, y, z; (iii) x+1, y+3/2, z+1/2; (iv) x, y+3/2, z1/2; (v) x, y+1, z+1; (vi) x+1, y1/2, z+1/2; (vii) x, y+3/2, z+1/2; (viii) x1, y+3/2, z1/2.

Experimental details

Crystal data
Chemical formulaC4H12N2·2C5H3N2O4·4H2O
Mr470.41
Crystal system, space groupMonoclinic, P21/c
Temperature (K)291
a, b, c (Å)8.3363 (13), 16.246 (3), 7.3930 (11)
β (°) 90.812 (3)
V3)1001.2 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.14
Crystal size (mm)0.15 × 0.14 × 0.12
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.980, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
5265, 1946, 1524
Rint0.051
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.147, 1.10
No. of reflections1946
No. of parameters169
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.41, 0.23

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008), DIAMOND (Brandenburg, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O5i0.84 (3)1.93 (3)2.746 (3)167 (3)
O2—H2···O4ii0.87 (3)1.65 (3)2.520 (2)175 (3)
N3—H3A···O40.88 (3)2.36 (3)2.918 (3)121 (2)
N3—H3A···N20.88 (3)2.01 (3)2.865 (3)162 (3)
N3—H3B···O3iii0.88 (3)2.20 (3)2.999 (3)150 (3)
O5—H5B···O60.85 (4)2.00 (4)2.831 (3)166 (3)
O5—H5A···O6iv0.92 (4)1.96 (4)2.833 (3)157 (3)
O6—H6C···O3v0.93 (3)1.85 (3)2.779 (3)173 (3)
O6—H6D···O3vi0.76 (3)2.14 (3)2.858 (3)158 (4)
C6—H6B···O5vii0.972.533.348 (4)141.7
C7—H7A···O1viii0.972.533.091 (3)116.8
Symmetry codes: (i) x+1, y, z; (ii) x+1, y+3/2, z+1/2; (iii) x, y+3/2, z1/2; (iv) x, y+1, z+1; (v) x+1, y1/2, z+1/2; (vi) x, y+3/2, z+1/2; (vii) x+1, y+1, z; (viii) x1, y+3/2, z1/2.
 

Acknowledgements

This research was supported financially by Nanjing University of Posts and Telecommunications (grant No. NY209032).

References

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First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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