Crystal structure of bis­(9H-6-amino­purin-1-ium) hexa­fluorido­silicate(IV) dihydrate

Belhouas, R.; Bouacida, S.; Boudaren, C.; Daran, J.-C.; Chtoun, E.H.

doi:10.1107/S2056989014027005

organic compounds

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Volume 71| Part 2| February 2015| Pages o72-o73

doi:10.1107/S2056989014027005

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Crystal structure of bis(9H-6-aminopurin-1-ium) hexafluoridosilicate(IV) dihydrate

Ratiba Belhouas,^a Sofiane Bouacida,^a,^b ^* Chaouki Boudaren,^a Jean-Claude Daran ^c and El Hossain Chtoun ^d

^aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Mentouri-Constantine, 25000, Algeria, ^bDépartement Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Oum El Bouaghi, Algeria, ^cLaboratoire de Chimie de Coordination, UPR CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex, France, and ^dUniversité Abdelmalek Essaadi, Faculté des Sciences, BP 2121 M'Hannech II, 93002 Tétouan, Morocco
^*Correspondence e-mail: bouacida_sofiane@yahoo.fr

Edited by M. Weil, Vienna University of Technology, Austria (Received 29 November 2014; accepted 9 December 2014; online 3 January 2015)

The asymmetric unit of the title compound, 2C₅H₆N₅⁺·SiF₆²⁻·2H₂O, contains one adeninium cation, half of a hexafluoridosilicate anion located on an inversion centre and one lattice water molecule. The adeninium cations are connected through N—H⋯N hydrogen bonds involving one H atom of the –NH₂ group and the H atom of the protonated N atom of the adenine ring system, forming centrosymmetric ring motifs of the type R₂²(10) and R₂²(8), respectively. The overall connection of the cation leads to the formation of planar ribbons parallel to (122). In the ribbons, slipped π–π stacking interactions, with a centroid-to-centroid distance of 3.6938 (9) Å, an interplanar distance of 3.455 Å and a slippage of 1.306 Å is observed. The hexafluoridosilicate anion and the water molecule are linked through O—H⋯F hydrogen bonds [ring motif R₄⁴(12)] into chains parallel to [100]. The cationic ribbons and anionic chains are finally connected through additional N—H⋯O, N—H⋯F and O—H⋯F hydrogen bonds into a three-dimensional network in which layers of adeninium cations and fluoridosilicate anions alternate parallel to (001).

Keywords: crystal structure; purinium cation; hexafluoridosilicate anion; hydrogen bonding.

CCDC reference: 1038389

1. Related literature

The title compound was prepared as part of our ongoing studies of hydrogen-bonding interactions in the crystal structures of protonated amines (Bouacida et al., 2005a ,b ,c ; 2006 ; Belhouas et al., 2012 ). For π–π stacking interactions, see: Janiak (2000 ).

2. Experimental

2.1. Crystal data

2C₅H₆N₅⁺·SiF₆²⁻·2H₂O
M_r = 450.42
Triclinic, $[P \overline 1]$
a = 5.7500 (7) Å
b = 7.8504 (3) Å
c = 10.0884 (6) Å
α = 79.141 (6)°
β = 84.534 (17)°
γ = 71.774 (9)°
V = 424.47 (6) Å³
Z = 1
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 295 K
0.55 × 0.12 × 0.07 mm

2.2. Data collection

Nonius KappaCCD diffractometer
4025 measured reflections
1923 independent reflections
1757 reflections with I > 2σ(I)
R_int = 0.018

2.3. Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.082
S = 1.03
1923 reflections
133 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W⋯F2ⁱ	0.85	1.88	2.7307 (14)	178
O1W—H2W⋯F3	0.80	1.95	2.7553 (14)	174
N1—H1⋯O1W	0.86	1.88	2.7059 (15)	162
N9—H9⋯N3ⁱⁱ	0.86	2.13	2.9378 (17)	157
N9—H9⋯F1ⁱⁱⁱ	0.86	2.54	3.0009 (14)	115
N6—H6A⋯F3ⁱ	0.86	1.98	2.7917 (14)	157
N6—H6A⋯F1^iv	0.86	2.61	3.2906 (15)	137
N6—H6B⋯N7^v	0.86	2.15	2.9648 (18)	159
Symmetry codes: (i) x+1, y, z; (ii) -x, -y+2, -z+1; (iii) x, y+1, z-1; (iv) -x+1, -y, -z+2; (v) -x+2, -y+1, -z+1.

Data collection: COLLECT (Otwinowski & Minor, 1997 ); cell refinement: DIRAX/LSQ (Duisenberg et al., 2003 ); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR92 (Burla et al., 2005 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), ORTEP-3 for Windows (Farrugia, 2012 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

CCDC reference: 1038389

Crystal structure: contains datablocks SiAde, I. DOI: 10.1107/S2056989014027005/wm5099sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989014027005/wm5099Isup2.hkl

checkCIF report

Related literature top

The title compound was prepared as part of our ongoing studies of hydrogen-bonding interactions in the crystal structures of protonated amines (Bouacida et al., 2005a,b,c; 2006; Belhouas et al., 2012). For π–π stacking interactions, see: Janiak (2000).

Experimental top

Crystals of the title compound were grown from aqueous solution by dissolving 1 mmol SiO₂ and 2 mmol adenine in hydrofluoric acid (HF). The solutions were slowly evaporated to dryness for a couple of weeks. Some colourless crystals were isolated under a polarizing microscope for X-ray diffraction analysis.

Computing details top

Data collection: COLLECT (Otwinowski & Minor, 1997); cell refinement: DIRAX/LSQ (Duisenberg et al., 2003); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR92 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

	Fig. 1. The principal structural units in the title compound. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radius. Hydrogen bonds are shown as dashed lines. [Symmetry code: (i) -x, -y, 2 - z]
	Fig. 2. Partial packing view of the title compound, showing the formation of R₂²(10) (A1) and R₂²(8) (A2) rings through N—H···N, N—H···O, N—H···F and O—H···F hydrogen bonds. For the sake of clarity, H atoms not involved in hydrogen bonding have been omitted. [Symmetry codes: (i) -x, y - 1/2, -z + 1/2; (ii) -x, y + 1/2, -z + 1/2; (iii) x, y - 1, z; (iv) -x, -y, -z + 1.].
	Fig. 3. Partial packing view showing chains formed between water molecules and fluoridosilicate anions through O—H···F hydrogen bonds. For the sake of clarity, the cationic counterparts have been omitted. [Symmetry code: (i) x + 1, y, z]
	Fig. 4. Packing view in a projection aproximately along [100] showing the formation of layers parallel to (001). Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

Bis(9H-6-aminopurin-1-ium) hexafluoridosilicate(IV) dihydrate top

Crystal data top

2C₅H₆N₅⁺·SiF₆²⁻·2H₂O	Z = 1
M_r = 450.42	F(000) = 230
Triclinic, P1	D_x = 1.762 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.7500 (7) Å	Cell parameters from 2981 reflections
b = 7.8504 (3) Å	θ = 5.2–27.5°
c = 10.0884 (6) Å	µ = 0.24 mm⁻¹
α = 79.141 (6)°	T = 295 K
β = 84.534 (17)°	Lath, colourless
γ = 71.774 (9)°	0.55 × 0.12 × 0.07 mm
V = 424.47 (6) Å³

Data collection top

Nonius KappaCCD diffractometer	1757 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.018
Detector resolution: 9 pixels mm^-1	θ_max = 27.5°, θ_min = 5.2°
CCD rotation images, thick slices scans	h = −6→7
4025 measured reflections	k = −10→10
1923 independent reflections	l = −13→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.082	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0373P)² + 0.1468P] where P = (F_o² + 2F_c²)/3
1923 reflections	(Δ/σ)_max = 0.001
133 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

2C₅H₆N₅⁺·SiF₆²⁻·2H₂O	γ = 71.774 (9)°
M_r = 450.42	V = 424.47 (6) Å³
Triclinic, P1	Z = 1
a = 5.7500 (7) Å	Mo Kα radiation
b = 7.8504 (3) Å	µ = 0.24 mm⁻¹
c = 10.0884 (6) Å	T = 295 K
α = 79.141 (6)°	0.55 × 0.12 × 0.07 mm
β = 84.534 (17)°

Data collection top

Nonius KappaCCD diffractometer	1757 reflections with I > 2σ(I)
4025 measured reflections	R_int = 0.018
1923 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.082	H-atom parameters constrained
S = 1.03	Δρ_max = 0.28 e Å⁻³
1923 reflections	Δρ_min = −0.22 e Å⁻³
133 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

	x	y	z	U_iso*/U_eq
Si1	0.0000	0.0000	1.0000	0.02519 (13)
F1	0.16598 (16)	−0.01595 (12)	1.13081 (8)	0.0417 (2)
F2	−0.25721 (16)	0.04669 (12)	1.09945 (9)	0.0432 (2)
F3	−0.03226 (17)	0.22671 (11)	0.95904 (9)	0.0410 (2)
O1W	0.36312 (19)	0.33709 (13)	0.99720 (11)	0.0411 (3)
H1W	0.4831	0.2480	1.0279	0.062*
H2W	0.2551	0.2970	0.9859	0.062*
N1	0.4082 (2)	0.56497 (15)	0.76571 (10)	0.0304 (2)
H1	0.4261	0.4920	0.8417	0.036*
N7	0.7063 (2)	0.69851 (15)	0.44077 (11)	0.0322 (3)
N9	0.3304 (2)	0.89656 (15)	0.41590 (11)	0.0339 (3)
H9	0.2111	0.9840	0.3789	0.041*
N6	0.8149 (2)	0.42421 (16)	0.70564 (12)	0.0384 (3)
H6A	0.8298	0.3513	0.7817	0.046*
H6B	0.9376	0.4154	0.6487	0.046*
N3	0.1313 (2)	0.80786 (16)	0.63114 (11)	0.0344 (3)
C6	0.6057 (2)	0.54850 (16)	0.67661 (12)	0.0277 (3)
C4	0.3254 (2)	0.79502 (17)	0.54071 (12)	0.0287 (3)
C5	0.5581 (2)	0.67381 (16)	0.55526 (12)	0.0268 (3)
C8	0.5605 (3)	0.83344 (18)	0.36060 (14)	0.0347 (3)
H8	0.6093	0.8810	0.2748	0.042*
C2	0.1861 (3)	0.68935 (19)	0.74132 (13)	0.0334 (3)
H2	0.0632	0.6901	0.8084	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Si1	0.0258 (2)	0.0253 (2)	0.0204 (2)	−0.00695 (18)	−0.00429 (17)	0.00622 (16)
F1	0.0428 (5)	0.0461 (5)	0.0328 (4)	−0.0095 (4)	−0.0160 (4)	0.0021 (3)
F2	0.0341 (4)	0.0502 (5)	0.0354 (4)	−0.0076 (4)	0.0041 (3)	0.0054 (4)
F3	0.0494 (5)	0.0291 (4)	0.0412 (5)	−0.0126 (4)	−0.0109 (4)	0.0080 (3)
O1W	0.0376 (6)	0.0361 (5)	0.0458 (6)	−0.0123 (4)	−0.0092 (4)	0.0080 (4)
N1	0.0364 (6)	0.0310 (5)	0.0209 (5)	−0.0091 (4)	−0.0034 (4)	0.0016 (4)
N7	0.0338 (6)	0.0308 (5)	0.0266 (5)	−0.0067 (5)	−0.0001 (4)	0.0027 (4)
N9	0.0354 (6)	0.0298 (5)	0.0279 (6)	−0.0023 (5)	−0.0052 (4)	0.0050 (4)
N6	0.0354 (6)	0.0376 (6)	0.0297 (6)	−0.0022 (5)	−0.0020 (5)	0.0106 (5)
N3	0.0323 (6)	0.0355 (6)	0.0286 (6)	−0.0024 (5)	−0.0022 (4)	−0.0017 (4)
C6	0.0328 (6)	0.0260 (6)	0.0232 (6)	−0.0086 (5)	−0.0038 (5)	−0.0009 (4)
C4	0.0328 (7)	0.0265 (6)	0.0244 (6)	−0.0061 (5)	−0.0044 (5)	−0.0021 (4)
C5	0.0306 (6)	0.0247 (5)	0.0229 (6)	−0.0064 (5)	−0.0028 (5)	−0.0009 (4)
C8	0.0380 (7)	0.0332 (6)	0.0270 (6)	−0.0079 (5)	−0.0013 (5)	0.0049 (5)
C2	0.0348 (7)	0.0361 (7)	0.0271 (6)	−0.0081 (5)	0.0008 (5)	−0.0051 (5)

Geometric parameters (Å, º) top

Si1—F1	1.6646 (8)	N9—C4	1.3605 (16)
Si1—F1ⁱ	1.6646 (8)	N9—C8	1.3637 (19)
Si1—F2	1.6867 (9)	N9—H9	0.8600
Si1—F2ⁱ	1.6867 (9)	N6—C6	1.3080 (17)
Si1—F3	1.7041 (8)	N6—H6A	0.8600
Si1—F3ⁱ	1.7041 (8)	N6—H6B	0.8600
O1W—H1W	0.8476	N3—C2	1.3015 (17)
O1W—H2W	0.8046	N3—C4	1.3632 (17)
N1—C2	1.3543 (18)	C6—C5	1.4081 (16)
N1—C6	1.3681 (17)	C4—C5	1.3803 (18)
N1—H1	0.8600	C8—H8	0.9300
N7—C8	1.3154 (17)	C2—H2	0.9300
N7—C5	1.3892 (16)

F1—Si1—F1ⁱ	180.000 (1)	C4—N9—H9	126.5
F1—Si1—F2	89.86 (5)	C8—N9—H9	126.5
F1ⁱ—Si1—F2	90.14 (5)	C6—N6—H6A	120.0
F1—Si1—F2ⁱ	90.14 (5)	C6—N6—H6B	120.0
F1ⁱ—Si1—F2ⁱ	89.86 (5)	H6A—N6—H6B	120.0
F2—Si1—F2ⁱ	180.0	C2—N3—C4	112.33 (12)
F1—Si1—F3	90.31 (4)	N6—C6—N1	120.97 (11)
F1ⁱ—Si1—F3	89.69 (4)	N6—C6—C5	125.23 (12)
F2—Si1—F3	89.68 (5)	N1—C6—C5	113.80 (11)
F2ⁱ—Si1—F3	90.32 (5)	N9—C4—N3	127.47 (12)
F1—Si1—F3ⁱ	89.69 (4)	N9—C4—C5	105.20 (11)
F1ⁱ—Si1—F3ⁱ	90.31 (4)	N3—C4—C5	127.32 (11)
F2—Si1—F3ⁱ	90.32 (5)	C4—C5—N7	111.11 (11)
F2ⁱ—Si1—F3ⁱ	89.68 (5)	C4—C5—C6	117.64 (12)
F3—Si1—F3ⁱ	180.000 (1)	N7—C5—C6	131.23 (12)
H1W—O1W—H2W	107.5	N7—C8—N9	113.25 (12)
C2—N1—C6	123.90 (11)	N7—C8—H8	123.4
C2—N1—H1	118.1	N9—C8—H8	123.4
C6—N1—H1	118.1	N3—C2—N1	125.00 (13)
C8—N7—C5	103.37 (11)	N3—C2—H2	117.5
C4—N9—C8	107.06 (11)	N1—C2—H2	117.5

Symmetry code: (i) −x, −y, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···F2ⁱⁱ	0.85	1.88	2.7307 (14)	178
O1W—H2W···F3	0.80	1.95	2.7553 (14)	174
N1—H1···O1W	0.86	1.88	2.7059 (15)	162
N9—H9···N3ⁱⁱⁱ	0.86	2.13	2.9378 (17)	157
N9—H9···F1^iv	0.86	2.54	3.0009 (14)	115
N6—H6A···F3ⁱⁱ	0.86	1.98	2.7917 (14)	157
N6—H6A···F1^v	0.86	2.61	3.2906 (15)	137
N6—H6B···N7^vi	0.86	2.15	2.9648 (18)	159

Symmetry codes: (ii) x+1, y, z; (iii) −x, −y+2, −z+1; (iv) x, y+1, z−1; (v) −x+1, −y, −z+2; (vi) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···F2ⁱ	0.85	1.88	2.7307 (14)	178.2
O1W—H2W···F3	0.80	1.95	2.7553 (14)	173.6
N1—H1···O1W	0.86	1.88	2.7059 (15)	161.7
N9—H9···N3ⁱⁱ	0.86	2.13	2.9378 (17)	157.3
N9—H9···F1ⁱⁱⁱ	0.86	2.54	3.0009 (14)	114.5
N6—H6A···F3ⁱ	0.86	1.98	2.7917 (14)	157.4
N6—H6A···F1^iv	0.86	2.61	3.2906 (15)	137.1
N6—H6B···N7^v	0.86	2.15	2.9648 (18)	158.5

Symmetry codes: (i) x+1, y, z; (ii) −x, −y+2, −z+1; (iii) x, y+1, z−1; (iv) −x+1, −y, −z+2; (v) −x+2, −y+1, −z+1.

Acknowledgements

We acknowledge MESRS and ATRST (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique Algérie) for financial support via the PNR programme.

References

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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Crystal structure of bis­­(9H-6-amino­purin-1-ium) hexa­fluorido­silicate(IV) dihydrate

1. Related literature

2. Experimental

2.1. Crystal data

2.2. Data collection

2.3. Refinement

Supporting information

Acknowledgements

References

organic compounds

Crystal structure of bis(9H-6-aminopurin-1-ium) hexafluoridosilicate(IV) dihydrate