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Acta Cryst. (2007). E63, m2901-m2902    [ doi:10.1107/S1600536807052890 ]

Tetraaquadiglycinemagnesium(II) hexaaquamagnesium(II) bis(sulfate)

K. Elayaraja, S. P. Parthiban, S. Ramalingom, G. Bocelli and S. N. Kalkura

Abstract top

In the title compound, [Mg(C2H5NO2)2(H2O)4][Mg(H2O)6](SO4)2, the MgII atoms of both dications lie on inversion centres, and each of them is in an octahedral coordination environment. The glycine molecule exists in the zwitterionic form. The [Mg(H2O)6]2+ and [Mg(C2H5NO2)2(H2O)4]2+ dications pack as alternate layers parallel to the ab plane, with the sulfate anions lying between them. The ions are linked to form a three-dimensional network by O-H...O and N-H...O hydrogen bonds.

Comment top

The glycine molecule is found to form many compounds with metal sulfates, metal halogenides and acids. There are many examples in the literature on glycine metallic sulfates (Peterková et al., 1991; Fleck & Bohatý, 2005). We report here the crystal structure of the title magnesium sulfate complex, with glycine.

The asymmetric unit of the title compound consists of one-half each of [Mg(H2O)6]2+ and [Mg(C2H5NO2)2(H2O)4]2+ dications, and one SO42− anion (Fig. 1). The MgII atoms of both dications lie on inversion centres, and they are in an octahedral coordination environment. The Mg—O distances of the [Mg(H2O)6]2+ dication lie in the range 2.048 (2) Å-2.105 (2) Å (Table 1), which is in good agreement with the literature value [2.045 (4)–2.099 (4) Å; Baur, 1964]. In the [Mg(C2H5NO2)2(H2O)4]2+ dication, the MgII atom is coordinated by two O atoms from two glycine ligands, and four water molecules. The Mg—O distance [2.128 (2) Å] involving the glycine molecule is longer than that involving the water molecule (Table 1).

The [Mg(H2O)6]2+ and [Mg(C2H5NO2)2(H2O)4]2+ dications pack as alternate layers parallel to the ab plane, with the sulfate anions lying between them. The complex cations and sulfate anions are linked to form a three-dimensional network by O—H···O and N—H···O hydrogen bonds (Table 2).

In the crystal structure, the glycine molecule exists in the zwitterionic form, which is normal for compounds of amino acids with inorganic salts. There are also many examples in the literature of glycinum and glycinate compounds (Muller et al., 1994). The non-hydrogen atoms of the glycine molecule are coplanar, with the caboxylate C—O distances being 1.269 (4) Å [C1—O7] and 1.239 (4) Å [C1—O8].

Related literature top

For related literature, see: Baur (1964); Fleck & Bohatý (2005); Muller et al. (1994); Peterková et al. (1991).

Experimental top

Colourless single crystals of the title compound were grown from a saturated aqueous solution. Glycine (3 g, 1.6 mol) was added to 25 ml of magnesium sulfate heptahydrate (40 g, 6.5 mol) solution at 313 K using a constant temperature water both. The solution was continuously stirred upto complete dissolution of glycine and the temperature was raised to 318 K to avoid nucleation during the filtration of the solution. This solution was subjected to solvent evaporation at room temperature and after 10 days, white tabular form of crystals were collected.

Refinement top

C-bound H atoms were positioned geometrically (C—H = 0.97 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C). The water H atoms were located and refined with distance restraints [O—H = 0.84 (1) Å and H···H = 1.37 (2) Å]. The three N—H distances were restrained to be equal.

Computing details top

Data collection: AED software/Program name? (Belletti, 2004); cell refinement: AED software/Program name? (Belletti, 2004); data reduction: AED software/Program name? (Belletti, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Atoms labelled with the suffixes a and b are generated by the symmetry operations (1 − x, −y, 1 − z) and (1 − x, 1 − y, −z), respectively. Only one sulfate anion is shown.
[Figure 2] Fig. 2. View of the crystal structure of the title compound.
Tetraaquadiglycinemagnesium(II) hexaaquamagnesium(II) bis(sulfate) top
Crystal data top
[Mg(C2H5NO2)2(H2O)4][Mg(H2O)6](SO4)2Z = 1
Mr = 571.04F000 = 300
Triclinic, P1Dx = 1.775 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 5.988 (3) ÅCell parameters from 36 reflections
b = 6.783 (2) Åθ = 7.9–17.5º
c = 13.391 (2) ŵ = 0.41 mm−1
α = 85.39 (2)ºT = 293 (2) K
β = 82.87 (2)ºBlock, colourless
γ = 82.88 (2)º0.21 × 0.19 × 0.16 mm
V = 534.4 (3) Å3
Data collection top
Siemens AED
diffractometer		Rint = 0.0000
Radiation source: fine-focus sealed tubeθmax = 25.5º
Monochromator: graphiteθmin = 1.5º
T = 293(2) Kh = −7→6
ω–2θ scansk = −6→8
Absorption correction: nonel = −12→16
1998 measured reflections1 standard reflections
1998 independent reflections every 50 reflections
1992 reflections with I > 2σ(I) intensity decay: none
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.066H atoms treated by a mixture of
independent and constrained refinement
wR(F2) = 0.171  w = 1/[σ2(Fo2) + (0.1149P)2 + 0.6843P]
where P = (Fo2 + 2Fc2)/3
S = 1.16(Δ/σ)max = 0.007
1998 reflectionsΔρmax = 0.94 e Å−3
201 parametersΔρmin = −1.07 e Å−3
18 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.37 (3)
Crystal data top
[Mg(C2H5NO2)2(H2O)4][Mg(H2O)6](SO4)2γ = 82.88 (2)º
Mr = 571.04V = 534.4 (3) Å3
Triclinic, P1Z = 1
a = 5.988 (3) ÅMo Kα
b = 6.783 (2) ŵ = 0.41 mm−1
c = 13.391 (2) ÅT = 293 (2) K
α = 85.39 (2)º0.21 × 0.19 × 0.16 mm
β = 82.87 (2)º
Data collection top
Siemens AED
diffractometer		Rint = 0.0000
Absorption correction: none1 standard reflections
1998 measured reflections every 50 reflections
1998 independent reflections intensity decay: none
1992 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.06618 restraints
wR(F2) = 0.171H atoms treated by a mixture of
independent and constrained refinement
S = 1.16Δρmax = 0.94 e Å−3
1998 reflectionsΔρmin = −1.07 e Å−3
201 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 > 2sigma(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
S10.01345 (11)0.91384 (10)0.18807 (5)0.0170 (3)
O10.1835 (4)1.0199 (3)0.12319 (18)0.0300 (6)
O2−0.0271 (4)0.7357 (3)0.13906 (17)0.0279 (6)
O3−0.2019 (4)1.0445 (3)0.20413 (17)0.0282 (6)
O40.0986 (4)0.8490 (4)0.28613 (17)0.0294 (6)
Mg10.50000.00000.50000.0184 (4)
O50.1910 (4)0.1538 (4)0.53615 (18)0.0318 (6)
H5B0.116 (6)0.206 (6)0.489 (2)0.044 (12)*
H5A0.101 (6)0.150 (7)0.5897 (17)0.046 (13)*
O60.4411 (4)0.0276 (4)0.34899 (15)0.0289 (6)
H6B0.326 (4)−0.002 (6)0.327 (3)0.040 (12)*
H6A0.547 (4)0.032 (6)0.302 (2)0.033 (11)*
O70.6414 (4)0.2747 (3)0.47278 (16)0.0271 (6)
O80.9719 (4)0.3338 (5)0.3855 (2)0.0440 (8)
N10.3922 (5)0.5024 (5)0.3456 (2)0.0317 (7)
H2N0.314 (7)0.580 (6)0.304 (3)0.039 (11)*
H1N0.369 (10)0.555 (8)0.404 (3)0.069 (17)*
H3N0.330 (10)0.392 (6)0.351 (5)0.073 (18)*
C10.7621 (5)0.3521 (5)0.3988 (2)0.0238 (7)
C20.6414 (6)0.4810 (5)0.3195 (2)0.0285 (7)
H2A0.69360.61170.31270.034*
H2B0.67940.42210.25500.034*
Mg20.50000.50000.00000.0186 (4)
O90.2942 (4)0.3973 (3)0.12778 (17)0.0273 (6)
H9B0.178 (4)0.478 (4)0.139 (3)0.026 (10)*
H9A0.264 (6)0.281 (2)0.126 (4)0.055 (14)*
O100.7834 (4)0.3371 (4)0.04927 (17)0.0283 (6)
H10B0.885 (6)0.292 (6)0.005 (2)0.041 (12)*
H10A0.777 (9)0.249 (6)0.097 (3)0.067 (17)*
O110.5499 (4)0.7319 (4)0.0805 (2)0.0351 (6)
H11B0.462 (5)0.835 (4)0.092 (3)0.040 (12)*
H11A0.678 (4)0.740 (6)0.098 (4)0.054 (14)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0201 (5)0.0216 (5)0.0101 (5)−0.0058 (3)−0.0018 (3)−0.0006 (3)
O10.0306 (13)0.0290 (12)0.0293 (13)−0.0113 (10)0.0076 (10)0.0004 (10)
O20.0299 (12)0.0317 (12)0.0255 (12)−0.0102 (9)−0.0044 (9)−0.0095 (9)
O30.0299 (13)0.0316 (12)0.0204 (11)0.0002 (9)0.0013 (9)0.0032 (9)
O40.0335 (13)0.0385 (13)0.0173 (11)−0.0045 (10)−0.0091 (9)0.0022 (9)
Mg10.0209 (7)0.0262 (8)0.0090 (7)−0.0065 (5)−0.0031 (5)0.0016 (5)
O50.0248 (12)0.0476 (14)0.0208 (12)0.0000 (10)−0.0015 (9)0.0021 (10)
O60.0265 (12)0.0520 (15)0.0109 (10)−0.0142 (10)−0.0034 (9)−0.0020 (9)
O70.0350 (13)0.0319 (12)0.0158 (11)−0.0122 (10)−0.0032 (9)0.0034 (9)
O80.0279 (13)0.0605 (18)0.0419 (16)−0.0090 (12)−0.0067 (11)0.0176 (13)
N10.0319 (16)0.0396 (17)0.0240 (14)−0.0035 (13)−0.0102 (12)0.0045 (12)
C10.0296 (16)0.0278 (15)0.0160 (14)−0.0101 (12)−0.0050 (12)0.0009 (11)
C20.0323 (17)0.0359 (17)0.0172 (15)−0.0078 (14)−0.0018 (12)0.0034 (13)
Mg20.0230 (8)0.0219 (7)0.0124 (7)−0.0054 (5)−0.0050 (5)−0.0015 (5)
O90.0310 (12)0.0282 (12)0.0227 (12)−0.0086 (10)−0.0001 (9)0.0011 (9)
O100.0315 (13)0.0344 (13)0.0171 (11)0.0021 (10)−0.0032 (9)0.0016 (9)
O110.0277 (13)0.0348 (13)0.0475 (15)−0.0036 (10)−0.0113 (11)−0.0199 (12)
Geometric parameters (Å, °) top
S1—O11.473 (2)N1—H1N0.87 (3)
S1—O31.474 (2)N1—H3N0.87 (3)
S1—O21.480 (2)C1—C21.517 (4)
S1—O41.482 (2)C2—H2A0.97
Mg1—O5i2.031 (2)C2—H2B0.97
Mg1—O52.031 (2)Mg2—O11ii2.048 (2)
Mg1—O6i2.085 (2)Mg2—O112.048 (2)
Mg1—O62.085 (2)Mg2—O10ii2.057 (2)
Mg1—O72.128 (2)Mg2—O102.057 (2)
Mg1—O7i2.128 (2)Mg2—O92.105 (2)
O5—H5B0.846 (10)Mg2—O9ii2.105 (2)
O5—H5A0.842 (10)O9—H9B0.835 (10)
O6—H6B0.838 (10)O9—H9A0.834 (10)
O6—H6A0.838 (10)O10—H10B0.844 (10)
O7—C11.269 (4)O10—H10A0.842 (10)
O8—C11.239 (4)O11—H11B0.837 (10)
N1—C21.481 (5)O11—H11A0.836 (10)
N1—H2N0.87 (3)
O1—S1—O3110.14 (14)O8—C1—O7125.9 (3)
O1—S1—O2109.60 (14)O8—C1—C2116.3 (3)
O3—S1—O2108.77 (14)O7—C1—C2117.8 (3)
O1—S1—O4109.55 (15)N1—C2—C1111.9 (3)
O3—S1—O4110.07 (14)N1—C2—H2A109.2
O2—S1—O4108.69 (14)C1—C2—H2A109.2
O5i—Mg1—O5180.00 (13)N1—C2—H2B109.2
O5i—Mg1—O6i89.18 (10)C1—C2—H2B109.2
O5—Mg1—O6i90.82 (10)H2A—C2—H2B107.9
O5i—Mg1—O690.82 (10)O11ii—Mg2—O11180.00 (13)
O5—Mg1—O689.18 (10)O11ii—Mg2—O10ii89.87 (10)
O6i—Mg1—O6180.0O11—Mg2—O10ii90.13 (10)
O5i—Mg1—O790.78 (10)O11ii—Mg2—O1090.13 (10)
O5—Mg1—O789.22 (10)O11—Mg2—O1089.87 (10)
O6i—Mg1—O792.84 (9)O10ii—Mg2—O10180.00 (12)
O6—Mg1—O787.16 (9)O11ii—Mg2—O992.24 (11)
O5i—Mg1—O7i89.22 (10)O11—Mg2—O987.76 (11)
O5—Mg1—O7i90.78 (10)O10ii—Mg2—O988.69 (10)
O6i—Mg1—O7i87.16 (9)O10—Mg2—O991.31 (10)
O6—Mg1—O7i92.84 (9)O11ii—Mg2—O9ii87.76 (11)
O7—Mg1—O7i180.0O11—Mg2—O9ii92.24 (11)
Mg1—O5—H5B119 (3)O10ii—Mg2—O9ii91.31 (10)
Mg1—O5—H5A131 (3)O10—Mg2—O9ii88.69 (10)
H5B—O5—H5A108 (2)O9—Mg2—O9ii180.00 (15)
Mg1—O6—H6B125 (3)Mg2—O9—H9B110 (3)
Mg1—O6—H6A122 (2)Mg2—O9—H9A115 (3)
H6B—O6—H6A110 (2)H9B—O9—H9A112 (3)
C1—O7—Mg1133.9 (2)Mg2—O10—H10B117 (3)
C2—N1—H2N116 (3)Mg2—O10—H10A123 (3)
C2—N1—H1N105 (4)H10B—O10—H10A106 (2)
H2N—N1—H1N107 (5)Mg2—O11—H11B128 (3)
C2—N1—H3N115 (4)Mg2—O11—H11A120 (3)
H2N—N1—H3N104 (5)H11B—O11—H11A111 (2)
H1N—N1—H3N109 (6)
O5i—Mg1—O7—C153.2 (3)Mg1—O7—C1—O8−90.2 (4)
O5—Mg1—O7—C1−126.8 (3)Mg1—O7—C1—C290.6 (4)
O6i—Mg1—O7—C1142.4 (3)O8—C1—C2—N1−176.7 (3)
O6—Mg1—O7—C1−37.6 (3)O7—C1—C2—N12.6 (4)
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O7iii0.87 (3)2.08 (5)2.939 (4)168 (4)
N1—H2N···O40.87 (3)2.12 (4)2.877 (4)145 (4)
N1—H3N···O60.87 (3)2.48 (4)3.195 (5)140 (5)
N1—H3N···O8iv0.87 (3)2.21 (6)2.865 (4)131 (4)
O5—H5A···O4v0.84 (1)1.92 (3)2.765 (4)178 (6)
O5—H5B···O8iv0.85 (1)1.83 (3)2.673 (4)175 (3)
O6—H6A···O3vi0.84 (1)1.87 (3)2.710 (4)176 (3)
O6—H6B···O4vii0.84 (1)1.95 (3)2.755 (4)163 (4)
O9—H9A···O1vii0.83 (1)1.90 (2)2.730 (3)178 (5)
O9—H9B···O20.84 (1)2.01 (3)2.808 (3)160 (3)
O10—H10A···O3vi0.84 (1)1.92 (4)2.755 (4)174 (5)
O10—H10B···O2ii0.84 (1)2.02 (3)2.800 (4)153 (3)
O11—H11A···O2viii0.84 (1)1.91 (3)2.747 (4)175 (4)
O11—H11B···O10.84 (1)1.98 (3)2.786 (4)162 (3)
Symmetry codes: (iii) −x+1, −y+1, −z+1; (iv) x−1, y, z; (v) −x, −y+1, −z+1; (vi) x+1, y−1, z; (vii) x, y−1, z; (ii) −x+1, −y+1, −z; (viii) x+1, y, z.
Selected geometric parameters (Å) top
Mg1—O52.031 (2)Mg2—O112.048 (2)
Mg1—O62.085 (2)Mg2—O102.057 (2)
Mg1—O72.128 (2)Mg2—O92.105 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O7i0.87 (3)2.08 (5)2.939 (4)168 (4)
N1—H2N···O40.87 (3)2.12 (4)2.877 (4)145 (4)
N1—H3N···O60.87 (3)2.48 (4)3.195 (5)140 (5)
N1—H3N···O8ii0.87 (3)2.21 (6)2.865 (4)131 (4)
O5—H5A···O4iii0.84 (1)1.92 (3)2.765 (4)178 (6)
O5—H5B···O8ii0.85 (1)1.83 (3)2.673 (4)175 (3)
O6—H6A···O3iv0.84 (1)1.87 (3)2.710 (4)176 (3)
O6—H6B···O4v0.84 (1)1.95 (3)2.755 (4)163 (4)
O9—H9A···O1v0.83 (1)1.90 (2)2.730 (3)178 (5)
O9—H9B···O20.84 (1)2.01 (3)2.808 (3)160 (3)
O10—H10A···O3iv0.84 (1)1.92 (4)2.755 (4)174 (5)
O10—H10B···O2vi0.84 (1)2.02 (3)2.800 (4)153 (3)
O11—H11A···O2vii0.84 (1)1.91 (3)2.747 (4)175 (4)
O11—H11B···O10.84 (1)1.98 (3)2.786 (4)162 (3)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y, z; (iii) −x, −y+1, −z+1; (iv) x+1, y−1, z; (v) x, y−1, z; (vi) −x+1, −y+1, −z; (vii) x+1, y, z.
Acknowledgements top

The authors thank Dr R. Malathi, Dr S. Selvanayagam, Professor M. N. Ponnuswamy and Professor D. Velmurugan, Department of Crystallography and Biophysics, University of Madras, for valuable discussions. This project was funded by DST, Government of India.

references
References top

Baur, W. H. (1964). Acta Cryst. 17, 1361–1369.

Belletti, D. (2004). Program name? Internal Report 1-04. Laboratorio di Strutturistica 'M. Nardelli', Parma, Italy,.

Fleck, M. & Bohatý, L. (2005). Acta Cryst. C61, m412–m416.

Muller, G., Maier, G.-M. & Lutz, M. (1994). Inorg. Chim. Acta, 218, 121–131.

Peterková, J., Podlahová, J., Loub, J. & Mička, Z. (1991). Acta Cryst. C47, 2664–2666.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Gottingen, Germany.

Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13.