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ISSN: 2056-9890

Di­ethyl­ammonium di­hydrogen orthophosphate

aInstitut für Kristallographie, Universität zu Köln, Greinstrasse 6, D-50939 Köln, Germany
*Correspondence e-mail: peter.held@uni-koeln.de

(Received 9 December 2013; accepted 8 January 2014; online 11 January 2014)

In the title molecular salt, [NH2(CH2CH3)2][H2PO4], two unique types of cations and anions, which are configurationally very similar, are present in the asymmetric unit. Both ions form sheets approximately parallel to (-1-1) linked by weak hydrogen bonds. The inter­connection within and between the sheets is reinforced by O—H⋯O and N—H⋯O hydrogen bonds involving the tetra­hedral H2PO4 anions and the ammonium groups.

Related literature

For preparative details, see: Hanna et al. (1999[Hanna, A. A., Ali, A. F. & Khalil, M. Sh. (1999). Indian J. Chem. Technol. 6, 43-47.]). For related structures, see: Averbuch-Pouchot et al. (1987[Averbuch-Pouchot, M. T., Durif, A. & Guitel, J.-C. (1987). Acta Cryst. C43, 1896-1898.]); Held (2003[Held, P. (2003). Z. Kristallogr. New Cryst. Struct. 218, 13-16.]).

[Scheme 1]

Experimental

Crystal data
  • C4H12N+·H2PO4

  • Mr = 171.13

  • Triclinic, [P \overline 1]

  • a = 8.3643 (6) Å

  • b = 8.8308 (15) Å

  • c = 11.6446 (12) Å

  • α = 88.219 (10)°

  • β = 83.649 (7)°

  • γ = 79.700 (7)°

  • V = 841.00 (18) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 295 K

  • 0.30 × 0.28 × 0.26 mm

Data collection
  • Nonius MACH3 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.858, Tmax = 0.998

  • 10831 measured reflections

  • 5096 independent reflections

  • 3164 reflections with I > 2σ(I)

  • Rint = 0.037

  • 3 standard reflections every 100 reflections intensity decay: −6.3%

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.119

  • S = 0.98

  • 5096 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.39 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O13—H13⋯O21i 0.82 1.78 2.5851 (19) 166
O14—H14⋯O12ii 0.82 1.83 2.6058 (19) 158
O24—H24⋯O22iii 0.82 1.95 2.585 (2) 133
O23—H23⋯O11i 0.82 1.84 2.620 (2) 158
N1—H1A⋯O22iv 0.90 1.88 2.779 (2) 174
N1—H1B⋯O21v 0.90 1.87 2.769 (2) 177
N2—H2A⋯O11vi 0.90 1.87 2.714 (2) 155
N2—H2B⋯O12 0.90 1.91 2.795 (2) 168
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x, -y+1, -z+1; (iii) -x+1, -y, -z; (iv) -x+1, -y+1, -z; (v) x-1, y+1, z; (vi) -x+1, -y+1, -z+1.

Data collection: CAD-4 (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4; data reduction: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ATOMS (Dowty, 2002[Dowty, E. (2002). ATOMS. Shape Software, Kingsport, Tennessee, USA.]) and ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.])'; software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

In the course of a systematic search for new 'double salts' of simple secondary amines and monovalent cations of various inorganic acids (Averbuch-Pouchot et al., 1987), the new structure of (C2N2H10)Li2(SO4)2 was described (Held, 2003). In continuation of these studies, sulfuric acid has been replaced with phosphoric acid in order to get an analogous lithium compound with a tetrahedral phosphoric unit. Moreover, ethylenediamine has been replaced with diethylamine. Surprisingly, lithium was not incorporated in the solid product and only the title compound, [NH2(CH2CH3)2]+[H2PO4]-, was finally obtained, the crystal structure of which is reported herein.

The crystal structure of [NH2(CH2CH3)2]+[H2PO4]- consists of diethylammonium cations, NH2(CH2CH3)2+, and dihydrogen orthophosphate anions, H2PO4- (Fig. 1). The ions form sheets approximately parallel to (112). The interconnection within and between the sheets is reinforced by a hydrogen bonding system between the tetrahedral dihydrogen orthophosphate groups on one hand and between the ammonium function and the H2PO4- units on the other (Figs. 2,3; Table 1).

Related literature top

For preparative details, see: Hanna et al. (1999). For related structures, see: Averbuch-Pouchot et al. (1987); Held (2003).

Experimental top

The title compound was obtained by reaction of an aqueous solution of lithium dihydrogenposphate with diethylammine in a stoichiometric ratio 1:1 (Hanna et al., 1999). The solution was kept at room temperature by cooling. The title compound crystallized by slow evaporation of the solvent at room temperature in form of colourless crystals with dimensions up to 4 mm within a few days.

Differential scanning calorimetry with a PerkinElmer DSC7 device in the temperature range from 183 K up to 293 K showed no significant feature.

Refinement top

The H atoms were clearly discernible from difference Fourier maps. However, to all hydrogen atoms riding model contraints were applied in the least squares refinement, with C—H = 0.96 Å for methyl H atoms (Uiso(H) = 1.5Ueq(C)), with C—H = 0.97 (Uiso(H) = 1.2Ueq(C)) for methylene H atoms, with N—H = 0.90 Å (Uiso(H) = 1.2Ueq(N)) and with O—H = 0.82 Å (Uiso(H) = 1.2Ueq(O)).

Structure description top

In the course of a systematic search for new 'double salts' of simple secondary amines and monovalent cations of various inorganic acids (Averbuch-Pouchot et al., 1987), the new structure of (C2N2H10)Li2(SO4)2 was described (Held, 2003). In continuation of these studies, sulfuric acid has been replaced with phosphoric acid in order to get an analogous lithium compound with a tetrahedral phosphoric unit. Moreover, ethylenediamine has been replaced with diethylamine. Surprisingly, lithium was not incorporated in the solid product and only the title compound, [NH2(CH2CH3)2]+[H2PO4]-, was finally obtained, the crystal structure of which is reported herein.

The crystal structure of [NH2(CH2CH3)2]+[H2PO4]- consists of diethylammonium cations, NH2(CH2CH3)2+, and dihydrogen orthophosphate anions, H2PO4- (Fig. 1). The ions form sheets approximately parallel to (112). The interconnection within and between the sheets is reinforced by a hydrogen bonding system between the tetrahedral dihydrogen orthophosphate groups on one hand and between the ammonium function and the H2PO4- units on the other (Figs. 2,3; Table 1).

For preparative details, see: Hanna et al. (1999). For related structures, see: Averbuch-Pouchot et al. (1987); Held (2003).

Computing details top

Data collection: CAD-4 (Enraf–Nonius, 1989); cell refinement: CAD-4 (Enraf–Nonius, 1989); data reduction: WinGX (Farrugia, 2012); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ATOMS (Dowty, 2002) and ORTEP-3 for Windows (Farrugia, 2012)'; software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular entities in the structure of [NH2(CH2CH3)2]+[H2PO4]-, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H labels were omitted for clarity.
[Figure 2] Fig. 2. The unit cell of [NH2(CH2CH3)2]+[H2PO4]- with colour scheme: N (orange), O (blue), [H2PO4]-tetrahedra (blue), P (red), C grey) and H (white). Hydrogen bonds (light blue) between H2PO4 tetrahedra and hydrogen bonds (orange) between ammonium groups and H2PO4 tetrahedra are shown.
[Figure 3] Fig. 3. Clinographic projection of eight unit cells of [NH2(CH2CH3)2]+[H2PO4]-. The ionic units form sheets approximately parallel to (112). Hydrogen bonds (grey) interconnect the sheets.
Diethylammonium dihydrogen orthophosphate top
Crystal data top
C4H12N+·H2PO4Z = 4
Mr = 171.13F(000) = 368
Triclinic, P1Dx = 1.352 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.3643 (6) ÅCell parameters from 25 reflections
b = 8.8308 (15) Åθ = 21.0–26.0°
c = 11.6446 (12) ŵ = 0.29 mm1
α = 88.219 (10)°T = 295 K
β = 83.649 (7)°Parallelepiped, colourless
γ = 79.700 (7)°0.30 × 0.28 × 0.26 mm
V = 841.00 (18) Å3
Data collection top
Nonius MACH3
diffractometer
3164 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.037
Graphite monochromatorθmax = 30.4°, θmin = 2.5°
ω/2θ scansh = 1111
Absorption correction: ψ scan
(North et al., 1968)
k = 1212
Tmin = 0.858, Tmax = 0.998l = 1616
10831 measured reflections3 standard reflections every 100 reflections
5096 independent reflections intensity decay: 6.3%
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.119H-atom parameters constrained
S = 0.98 w = 1/[σ2(Fo2) + (0.0553P)2 + 0.1855P]
where P = (Fo2 + 2Fc2)/3
5096 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.39 e Å3
Crystal data top
C4H12N+·H2PO4γ = 79.700 (7)°
Mr = 171.13V = 841.00 (18) Å3
Triclinic, P1Z = 4
a = 8.3643 (6) ÅMo Kα radiation
b = 8.8308 (15) ŵ = 0.29 mm1
c = 11.6446 (12) ÅT = 295 K
α = 88.219 (10)°0.30 × 0.28 × 0.26 mm
β = 83.649 (7)°
Data collection top
Nonius MACH3
diffractometer
3164 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.037
Tmin = 0.858, Tmax = 0.9983 standard reflections every 100 reflections
10831 measured reflections intensity decay: 6.3%
5096 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.119H-atom parameters constrained
S = 0.98Δρmax = 0.37 e Å3
5096 reflectionsΔρmin = 0.39 e Å3
181 parameters
Special details top

Experimental. A suitable single-crystal was carefully selected under a polarizing microscope and mounted in a glass capillary.

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
P10.16567 (5)0.37327 (5)0.60452 (4)0.02736 (12)
O110.33132 (15)0.27994 (16)0.61779 (12)0.0362 (3)
O120.16402 (16)0.53915 (15)0.56977 (12)0.0365 (3)
O130.05039 (16)0.36883 (18)0.71998 (12)0.0426 (4)
H130.09860.31190.76690.064*
O140.08747 (18)0.29249 (16)0.51243 (13)0.0418 (3)
H140.00340.34160.50370.063*
P20.67897 (6)0.09624 (6)0.11311 (4)0.03332 (13)
O210.83801 (17)0.20760 (18)0.10779 (12)0.0431 (4)
O220.68455 (18)0.04631 (17)0.03943 (13)0.0454 (4)
O230.6256 (2)0.04343 (17)0.24046 (13)0.0502 (4)
H230.61380.11850.28160.075*
O240.54703 (19)0.18437 (17)0.07620 (15)0.0540 (4)
H240.45880.12590.07840.081*
C110.2499 (4)0.5728 (3)0.0009 (3)0.0663 (7)
H11A0.30100.46770.01430.100*
H11B0.17900.57920.07020.100*
H11C0.33220.63460.00400.100*
C120.1521 (3)0.6303 (3)0.0985 (2)0.0551 (6)
H12A0.22340.62230.17050.066*
H12B0.07000.56680.10430.066*
N10.0712 (2)0.7927 (2)0.08051 (14)0.0389 (4)
H1A0.14620.84720.06290.047*
H1B0.00490.79620.01920.047*
C130.0092 (4)0.8696 (3)0.1815 (2)0.0633 (7)
H13A0.05180.97670.16340.076*
H13B0.07190.86680.24810.076*
C140.1460 (4)0.7938 (4)0.2114 (2)0.0674 (8)
H14A0.19390.84670.27590.101*
H14B0.22750.79780.14610.101*
H14C0.10400.68840.23110.101*
C210.2697 (4)0.9059 (3)0.4832 (3)0.0767 (9)
H21A0.21251.00880.47220.115*
H21B0.37930.90910.49880.115*
H21C0.21440.85810.54720.115*
C220.2739 (3)0.8160 (3)0.3772 (2)0.0530 (6)
H22A0.32830.86500.31220.064*
H22B0.16320.81380.36080.064*
N20.36206 (19)0.65586 (19)0.39194 (14)0.0387 (4)
H2A0.46430.65960.40760.046*
H2B0.31180.61260.45350.046*
C230.3717 (3)0.5556 (3)0.2904 (2)0.0524 (6)
H23A0.42930.59930.22420.063*
H23B0.26220.55200.27210.063*
C240.4584 (3)0.3952 (3)0.3128 (2)0.0599 (7)
H24A0.46270.33370.24560.090*
H24B0.40050.35090.37730.090*
H24C0.56750.39830.32970.090*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.0192 (2)0.0322 (2)0.0307 (2)0.00441 (17)0.00520 (17)0.00718 (18)
O110.0191 (6)0.0458 (8)0.0417 (8)0.0025 (5)0.0037 (5)0.0122 (6)
O120.0325 (7)0.0347 (7)0.0448 (8)0.0102 (6)0.0119 (6)0.0110 (6)
O130.0254 (7)0.0588 (9)0.0371 (7)0.0040 (6)0.0011 (6)0.0160 (7)
O140.0397 (8)0.0365 (7)0.0507 (9)0.0017 (6)0.0193 (7)0.0035 (6)
P20.0281 (2)0.0350 (3)0.0388 (3)0.00980 (19)0.0092 (2)0.0130 (2)
O210.0312 (7)0.0590 (9)0.0344 (7)0.0011 (6)0.0025 (6)0.0143 (7)
O220.0428 (8)0.0464 (8)0.0549 (9)0.0229 (7)0.0227 (7)0.0253 (7)
O230.0586 (10)0.0409 (8)0.0447 (9)0.0048 (7)0.0021 (7)0.0069 (7)
O240.0470 (9)0.0392 (8)0.0850 (12)0.0202 (7)0.0334 (8)0.0228 (8)
C110.0626 (17)0.0470 (14)0.092 (2)0.0091 (12)0.0194 (16)0.0012 (14)
C120.0502 (14)0.0593 (15)0.0571 (15)0.0138 (11)0.0012 (11)0.0197 (12)
N10.0366 (9)0.0481 (10)0.0361 (9)0.0195 (8)0.0036 (7)0.0022 (7)
C130.0762 (19)0.0782 (18)0.0452 (14)0.0365 (15)0.0179 (13)0.0191 (13)
C140.0759 (19)0.081 (2)0.0537 (15)0.0226 (15)0.0304 (14)0.0031 (14)
C210.074 (2)0.0466 (15)0.103 (2)0.0002 (14)0.0004 (18)0.0028 (16)
C220.0306 (10)0.0525 (13)0.0738 (17)0.0069 (9)0.0045 (10)0.0280 (12)
N20.0265 (8)0.0485 (10)0.0427 (9)0.0117 (7)0.0050 (7)0.0104 (8)
C230.0418 (12)0.0802 (18)0.0401 (12)0.0225 (12)0.0078 (10)0.0027 (12)
C240.0503 (14)0.0718 (18)0.0595 (16)0.0205 (13)0.0058 (12)0.0170 (13)
Geometric parameters (Å, º) top
P1—O111.5013 (13)C13—C141.501 (4)
P1—O121.5056 (14)C13—H13A0.9700
P1—O141.5673 (14)C13—H13B0.9700
P1—O131.5691 (14)C14—H14A0.9600
O13—H130.8200C14—H14B0.9600
O14—H140.8200C14—H14C0.9600
P2—O211.5027 (14)C21—C221.482 (4)
P2—O221.5060 (14)C21—H21A0.9600
P2—O231.5613 (16)C21—H21B0.9600
P2—O241.5624 (15)C21—H21C0.9600
O23—H230.8200C22—N21.487 (3)
O24—H240.8200C22—H22A0.9700
C11—C121.497 (4)C22—H22B0.9700
C11—H11A0.9600N2—C231.485 (3)
C11—H11B0.9600N2—H2A0.9000
C11—H11C0.9600N2—H2B0.9000
C12—N11.483 (3)C23—C241.501 (4)
C12—H12A0.9700C23—H23A0.9700
C12—H12B0.9700C23—H23B0.9700
N1—C131.503 (3)C24—H24A0.9600
N1—H1A0.9000C24—H24B0.9600
N1—H1B0.9000C24—H24C0.9600
O11—P1—O12115.38 (8)N1—C13—H13B109.1
O11—P1—O14107.71 (8)H13A—C13—H13B107.9
O12—P1—O14109.31 (8)C13—C14—H14A109.5
O11—P1—O13110.08 (7)C13—C14—H14B109.5
O12—P1—O13108.20 (8)H14A—C14—H14B109.5
O14—P1—O13105.74 (9)C13—C14—H14C109.5
P1—O13—H13109.5H14A—C14—H14C109.5
P1—O14—H14109.5H14B—C14—H14C109.5
O21—P2—O22114.38 (9)C22—C21—H21A109.5
O21—P2—O23109.41 (8)C22—C21—H21B109.5
O22—P2—O23107.50 (9)H21A—C21—H21B109.5
O21—P2—O24107.55 (9)C22—C21—H21C109.5
O22—P2—O24110.16 (8)H21A—C21—H21C109.5
O23—P2—O24107.65 (10)H21B—C21—H21C109.5
P2—O23—H23109.5C21—C22—N2110.6 (2)
P2—O24—H24109.5C21—C22—H22A109.5
C12—C11—H11A109.5N2—C22—H22A109.5
C12—C11—H11B109.5C21—C22—H22B109.5
H11A—C11—H11B109.5N2—C22—H22B109.5
C12—C11—H11C109.5H22A—C22—H22B108.1
H11A—C11—H11C109.5C23—N2—C22114.70 (18)
H11B—C11—H11C109.5C23—N2—H2A108.6
N1—C12—C11110.87 (19)C22—N2—H2A108.6
N1—C12—H12A109.5C23—N2—H2B108.6
C11—C12—H12A109.5C22—N2—H2B108.6
N1—C12—H12B109.5H2A—N2—H2B107.6
C11—C12—H12B109.5N2—C23—C24111.64 (19)
H12A—C12—H12B108.1N2—C23—H23A109.3
C12—N1—C13115.31 (19)C24—C23—H23A109.3
C12—N1—H1A108.4N2—C23—H23B109.3
C13—N1—H1A108.4C24—C23—H23B109.3
C12—N1—H1B108.4H23A—C23—H23B108.0
C13—N1—H1B108.4C23—C24—H24A109.5
H1A—N1—H1B107.5C23—C24—H24B109.5
C14—C13—N1112.3 (2)H24A—C24—H24B109.5
C14—C13—H13A109.1C23—C24—H24C109.5
N1—C13—H13A109.1H24A—C24—H24C109.5
C14—C13—H13B109.1H24B—C24—H24C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O13—H13···O21i0.821.782.5851 (19)166
O14—H14···O12ii0.821.832.6058 (19)158
O24—H24···O22iii0.821.952.585 (2)133
O23—H23···O11i0.821.842.620 (2)158
N1—H1A···O22iv0.901.882.779 (2)174
N1—H1B···O21v0.901.872.769 (2)177
N2—H2A···O11vi0.901.872.714 (2)155
N2—H2B···O120.901.912.795 (2)168
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+1, z+1; (iii) x+1, y, z; (iv) x+1, y+1, z; (v) x1, y+1, z; (vi) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O13—H13···O21i0.821.782.5851 (19)166.2
O14—H14···O12ii0.821.832.6058 (19)158.0
O24—H24···O22iii0.821.952.585 (2)133.2
O23—H23···O11i0.821.842.620 (2)157.8
N1—H1A···O22iv0.901.882.779 (2)174.4
N1—H1B···O21v0.901.872.769 (2)177.0
N2—H2A···O11vi0.901.872.714 (2)155.0
N2—H2B···O120.901.912.795 (2)167.8
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+1, z+1; (iii) x+1, y, z; (iv) x+1, y+1, z; (v) x1, y+1, z; (vi) x+1, y+1, z+1.
 

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