Bis(guanidinium) bis­(4-hydroxy­pyridine-2,6-dicarboxyl­ato-κ3O2,N,O6)nickel­ate(II) dihydrate

Aghabozorg, H.; Motyeian, E.; Attar Gharamaleki, J.; Soleimannejad, J.; Ghadermazi, M.; Spey Sharon, E.

doi:10.1107/S1600536807065026

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 1| January 2008| Pages m144-m145

https://doi.org/10.1107/S1600536807065026

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Bis(guanidinium) bis(4-hydroxypyridine-2,6-dicarboxylato-κ³O²,N,O⁶)nickelate(II) dihydrate

Hossein Aghabozorg,^a ^* Elham Motyeian,^a Jafar Attar Gharamaleki,^a Janet Soleimannejad,^b Mohammad Ghadermazi ^c and Elizabeth Spey Sharon ^d

^aFaculty of Chemistry, Teacher Training University, Tehran, Iran, ^bFaculty of Science, Department of Chemistry, Ilam University, Iran, ^cDepartment of Chemistry, Faculty of Science, University of Kurdistan, Sanandaj, Iran, and ^dDepartment of Chemistry, Sheffield University, Sheffield S3 7HF, England
^*Correspondence e-mail: haghabozorg@yahoo.com

(Received 5 November 2007; accepted 2 December 2007; online 12 December 2007)

The reaction of nickel(II) nitrate hexahydrate, guanidine (G) and 4-hydroxypyridine-2,6-dicarboxylic acid (hypydcH₂) in a 1:2:2 molar ratio in aqueous solution resulted in the formation of the title compound, (CH₆N₃)₂[Ni(C₇H₃NO₅)₂]·2H₂O or (GH)₂[Ni(hypydc)₂]·2H₂O. The six donor atoms of the two 4-hydroxypyridine-2,6-dicarboxylate or (hypydc)²⁻ ligands form a distorted octahedral arrangement around the Ni^II centre. Considerable C—O⋯π stacking interactions between the CO groups of carboxylate fragments and the pyridine rings of (hypydc)²⁻ with a distance of 3.3212 (8) Å are observed. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types O—H⋯O and N—H⋯O), ion pairing, and π–π [centroid–centroid distance 3.8037 (5) Å], N—H⋯π and C—O⋯π stacking interactions connect the various components into a supramolecular structure.

Related literature

For related literature, see: Aghabozorg, Attar Gharamaleki et al. (2007a , 2007b ); Aghabozorg, Daneshvar et al. (2007 ).

Experimental

Crystal data

(CH₆N₃)₂[Ni(C₇H₃NO₅)₂]·2H₂O
M_r = 577.13
Triclinic, $[P \overline 1]$
a = 8.9253 (6) Å
b = 9.9060 (6) Å
c = 13.2186 (9) Å
α = 101.415 (3)°
β = 103.099 (3)°
γ = 91.938 (3)°
V = 1111.99 (13) Å³
Z = 2
Mo Kα radiation
μ = 0.96 mm⁻¹
T = 150 (2) K
0.50 × 0.32 × 0.15 mm

Data collection

Bruker SMART 1000 diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.647, T_max = 0.870
46516 measured reflections
10497 independent reflections
9650 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.076
S = 1.06
10497 reflections
334 parameters
H-atom parameters constrained
Δρ_max = 0.56 e Å⁻³
Δρ_min = −0.61 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Ni1—N2	1.9665 (6)
Ni1—N1	1.9700 (6)
Ni1—O1	2.1088 (6)
Ni1—O10	2.1387 (6)
Ni1—O6	2.1477 (6)
Ni1—O5	2.2149 (6)

N2—Ni1—N1	171.30 (3)
O1—Ni1—O5	154.97 (2)
O10—Ni1—O6	154.87 (2)
O1—Ni1—O10	93.41 (3)
O6—Ni1—O5	91.30 (2)

Table 2
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the N1/C2–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3C⋯O6ⁱ	0.90	1.71	2.5901 (8)	166
O8—H8⋯O5ⁱⁱ	0.90	1.84	2.7057 (9)	160
O11—H11A⋯O9ⁱⁱⁱ	0.90	1.86	2.7106 (9)	156
O11—H11B⋯O2^iv	0.90	1.88	2.7464 (9)	161
O12—H12B⋯O11ⁱⁱ	0.90	2.15	3.0425 (12)	172
O12—H12A⋯O5	0.90	2.15	3.0244 (13)	164
O12—H12A⋯O4	0.90	2.64	3.3823 (12)	141
N3—H3A⋯O4^v	0.90	2.15	2.9307 (10)	144
N3—H3B⋯O10	0.90	2.07	2.8817 (10)	149
N4—H4A⋯O4^v	0.90	1.97	2.8072 (11)	154
N4—H4B⋯O11^vi	0.90	2.06	2.9161 (10)	159
N5—H5A⋯O10	0.90	2.19	2.9887 (10)	148
N5—H5B⋯O2^vii	0.90	1.98	2.8656 (10)	169
N6—H6A⋯O7^viii	0.90	2.28	3.0178 (11)	139
N6—H6A⋯O1	0.90	2.49	3.0038 (9)	117
N6—H6B⋯O3^vii	0.90	2.55	3.2320 (11)	133
N7—H7A⋯O9ⁱⁱⁱ	0.90	2.01	2.8999 (10)	172
N7—H7B⋯O12^ix	0.90	1.93	2.8282 (13)	176
N8—H8A⋯O7^viii	0.90	1.94	2.7993 (10)	158
N8—H8B⋯O11	0.90	1.99	2.8847 (10)	174
N5—H5A⋯Cg1	0.90	3.47	3.362 (7)	75
Symmetry codes: (i) -x, -y+1, -z; (ii) -x+1, -y+1, -z+1; (iii) -x+1, -y, -z+1; (iv) -x, -y, -z+1; (v) -x+1, -y+1, -z; (vi) x, y, z-1; (vii) -x, -y, -z; (viii) -x, -y+1, -z+1; (ix) x, y-1, z.

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2005 ) and Mercury (Version 1.4.2; Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536807065026/om2189sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807065026/om2189Isup2.hkl

checkCIF report

Comment top

The non-covalent interactions such as ion pairing, hydrogen bonding and π–π stacking are observed in these ionic compounds. The importance of weak hydrogen bonds in the context of crystal engineering, molecular recognition and supramolecular chemistry has been well recognized in recent years. Recently, we have defined a plan to prepare water soluble proton transfer compounds as novel self assembled systems that can function as suitable ligands in the synthesis of metal complexes. In this regard, we have reported cases in which proton transfers from pyridine-2,6-dicarboxylic acid, pydcH₂, and benzene-1,2,4,5-tetracarboxylicacid, btcH₄, to propane-1,3-diamine (pn) and 1,10-phenanthroline, (phen), resulted in the formation of novel self-assembled (pnH₂)(pydc)^.(pydcH₂)^.2.5H₂O, (pnH₂)₂(btc)^.2H₂O and (phenH)₄(btcH₃)₂(btcH₂) systems, respectively. The resulting compounds with some remaining sites as electron donors can coordinate to metallic ions (Aghabozorg, Attar Gharamaleki et al., 2007a,b; Aghabozorg, Daneshvar et al., 2007).

The molecular structure of the title compound is presented in Fig. 1. The Ni^II atom is six-coordinated by two 4-hydroxypyridine-2,6-dicarboxylate, or (hypydc)^2-, groups, i.e. each (hypydc)^2–is coordinated through one pyridine N atom and two carboxylate O atoms (Table 1). N1 and N2 atoms of the two (hypydc)^2–fragments occupy the axial positions, while atoms O1, O5, O6 and O10 form the equatorial plane [with Ni—O distances ranging from 2.1088 (6) to 2.2150 (6) Å]. The N1—Ni1—N2 angle [171.30 (3)°] deviates from linearity. Therefore, the coordination around Ni^II is distorted octahedral. The O5—Ni1—O6 and O1—Ni1—O10 angles are equal to 91.30 (2) and 93.41 (3)°, respectively. On the other hand, O1—Ni1—O6—C8 and O10—Ni1—O5—C7 torsion angles are 93.20 (5) and 92.27 (5) Å, respectively indicating that two (hypydc)^2- units are almost perpendicular to each other.

A noticeable feature of the title compound is the presence of N—H···π stacking interactions between N—H group of guanidinium ions with aromatic rings of (hypydc)^2- units. The H···π distance (measured to the centre of phenyl ring) is 3.475Å for N5—H5A···Cg1 [Cg1 is the centroid of N1/C2—C6 ring]. There is also π···π stacking interaction betweentwo aromatic rings of (hypydc)^2–units, with distance of 3.8037 (5) Å [-x, 1 - y, -z] (Fig. 2).

Also a considerable C—O···π stacking interactions between CO groups of carboxylate fragments with aromatic rings of 4-hydroxypyridine-2,6-dicarboxylate with distances of 3.321 (8) Å for C8—O7···Cg2 (-x, 1 - y, 1 - z) [Cg2 is the centroid for N2/C9—C13 ring] are observed in the prepared compound (Fig. 3). In the crystal structure, a wide range of non-covalent interactions consisting of hydrogen bonding (of the type of O—H···O and N—H···O with D···A ranging from 2.5901 (8) Å to 3.3823 (12) Å), ion pairing, π···π, N—H···π and C—O···π stacking connect the various components into a supramolecular structure (Table 2, Figs. 4 and 5).

Related literature top

For related literature, see: Aghabozorg, Attar Gharamaleki et al. (2007a, 2007b); Aghabozorg, Daneshvar et al. (2007).

Experimental top

An aqueous solution of sodium hydroxide (80 mg, 2 mmol) was added to guanidine hydrochloride (200 mg, 2 mmol) in a 1:1 molar ratio. The resulting suspension was stirred for 1 h and filtered. An aqueous solution of Ni(NO₃)₂.6H₂O (290 mg, 1 mmol) and 4-hydroxypyridine-2,6-dicarboxylic (360 mg, 2 mmol) acid was added to the filtered solution in a 1:2 molar ratio, and the reaction mixture was heated to boiling point for 2 h. Green crystals were obtained from the solution after two days at room temperature.

Structure description top

For related literature, see: Aghabozorg, Attar Gharamaleki et al. (2007a, 2007b); Aghabozorg, Daneshvar et al. (2007).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2005) and Mercury (Version 1.4.2; Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top

	Fig. 1. The structure of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. π···π Stacking interaction between two aromatic rings of (hypydc)^2– units, with distance of 3.8037 (5) Å [-x, 1 - y, -z]; N—H···π stacking interaction between N—H groups of guanidinium ions with aromatic rings of (hypydc)^2- units. The H···π distance (measured to the centre of phenyl ring) is 2.96 Å for N5—H5A···Cg1 [Cg1 is the centroid of N1/C2—C6 ring].
	Fig. 3. C—O···π stacking interactions between CO groups of carboxylate fragments with aromatic rings of 4-hydroxypyridine-2,6-dicarboxylate with distances of 3.321 (8) Å for C8—O7···Cg2 (-x, 1 - y, 1 - z) [Cg2 is the centroid for N2/C9—C13 ring].
	Fig. 4. A layered packing diagram. The space between the two layers of [Ni(hypydc)₂]^2- fragments is filled with a layer of (GH)⁺ cations and water molecules.
	Fig. 5. The crystal packing of the title compound view down the a axis; hydrogen bonds are shown as dashed lines.

Bis(guanidinium) bis(4-hydroxypyridine-2,6-dicarboxylato-κ³O²,N,O⁶)nickelate(II) dihydrate top

Crystal data top

(CH₆N₃)₂[Ni(C₇H₃NO₅)₂]·2H₂O	Z = 2
M_r = 577.13	F(000) = 596
Triclinic, P1	D_x = 1.724 Mg m⁻³
a = 8.9253 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.9060 (6) Å	Cell parameters from 9699 reflections
c = 13.2186 (9) Å	θ = 2.4–36.3°
α = 101.415 (3)°	µ = 0.96 mm⁻¹
β = 103.099 (3)°	T = 150 K
γ = 91.938 (3)°	Block, green
V = 1111.99 (13) Å³	0.50 × 0.32 × 0.15 mm

Data collection top

Bruker SMART 1000 diffractometer	10497 independent reflections
Radiation source: fine-focus sealed tube	9650 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
Detector resolution: 8.3 pixels mm^-1	θ_max = 36.4°, θ_min = 1.6°
ω scans	h = −14→11
Absorption correction: multi-scan (SADABS; Bruker, 1998)	k = −16→16
T_min = 0.647, T_max = 0.870	l = −21→21
46516 measured reflections

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.076	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.043P)² + 0.2702P] where P = (F_o² + 2F_c²)/3
10497 reflections	(Δ/σ)_max = 0.002
334 parameters	Δρ_max = 0.56 e Å⁻³
0 restraints	Δρ_min = −0.61 e Å⁻³

Crystal data top

(CH₆N₃)₂[Ni(C₇H₃NO₅)₂]·2H₂O	γ = 91.938 (3)°
M_r = 577.13	V = 1111.99 (13) Å³
Triclinic, P1	Z = 2
a = 8.9253 (6) Å	Mo Kα radiation
b = 9.9060 (6) Å	µ = 0.96 mm⁻¹
c = 13.2186 (9) Å	T = 150 K
α = 101.415 (3)°	0.50 × 0.32 × 0.15 mm
β = 103.099 (3)°

Data collection top

Bruker SMART 1000 diffractometer	10497 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	9650 reflections with I > 2σ(I)
T_min = 0.647, T_max = 0.870	R_int = 0.019
46516 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	0 restraints
wR(F²) = 0.076	H-atom parameters constrained
S = 1.06	Δρ_max = 0.56 e Å⁻³
10497 reflections	Δρ_min = −0.61 e Å⁻³
334 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
Ni1	0.173117 (11)	0.423258 (10)	0.259400 (7)	0.01287 (3)
O1	−0.00784 (7)	0.27245 (6)	0.24384 (5)	0.01774 (10)
O2	−0.16765 (9)	0.11004 (7)	0.12138 (5)	0.02439 (13)
O3	−0.02586 (9)	0.20971 (7)	−0.21698 (5)	0.02167 (12)
H3C	−0.0206	0.2745	−0.2554	0.026*
O4	0.35691 (8)	0.60277 (7)	0.04763 (5)	0.02381 (12)
O5	0.31707 (7)	0.56247 (6)	0.20082 (5)	0.01687 (10)
O6	0.05225 (7)	0.59263 (6)	0.32052 (4)	0.01635 (10)
O7	0.02582 (8)	0.72029 (7)	0.47531 (5)	0.02065 (11)
O8	0.37838 (8)	0.46857 (7)	0.73456 (5)	0.02054 (11)
H8	0.4719	0.4367	0.7525	0.025*
O9	0.51375 (8)	0.19318 (7)	0.39007 (5)	0.02143 (11)
O10	0.34554 (7)	0.27853 (6)	0.26981 (5)	0.01768 (10)
O11	0.32536 (8)	−0.04310 (7)	0.73709 (5)	0.02032 (11)
H11A	0.3814	−0.1076	0.7089	0.024*
H11B	0.2653	−0.0814	0.7719	0.024*
O12	0.37899 (13)	0.87354 (12)	0.25296 (8)	0.0491 (3)
H12B	0.4704	0.9157	0.2539	0.059*
H12A	0.3664	0.7820	0.2257	0.059*
N1	0.09970 (7)	0.36856 (6)	0.10372 (5)	0.01309 (10)
N2	0.25270 (7)	0.44832 (6)	0.41390 (5)	0.01274 (10)
N3	0.50285 (9)	0.28895 (8)	0.10335 (6)	0.02072 (13)
H3A	0.5659	0.3475	0.0847	0.025*
H3B	0.4860	0.3064	0.1691	0.025*
N4	0.43549 (11)	0.16824 (9)	−0.06920 (7)	0.02808 (17)
H4A	0.5014	0.2288	−0.0833	0.034*
H4B	0.3907	0.0927	−0.1182	0.034*
N5	0.32885 (10)	0.09767 (8)	0.05716 (6)	0.02313 (14)
H5A	0.3226	0.1189	0.1254	0.028*
H5B	0.2719	0.0285	0.0071	0.028*
N6	0.12908 (10)	0.08178 (8)	0.38427 (6)	0.02258 (13)
H6A	0.0636	0.1481	0.3920	0.027*
H6B	0.1274	0.0351	0.3182	0.027*
N7	0.29526 (10)	−0.06930 (9)	0.45012 (7)	0.02577 (15)
H7A	0.3483	−0.1044	0.5041	0.031*
H7B	0.3174	−0.0873	0.3859	0.031*
N8	0.18342 (10)	0.08088 (8)	0.56283 (6)	0.02222 (13)
H8A	0.1141	0.1442	0.5680	0.027*
H8B	0.2214	0.0388	0.6166	0.027*
C1	−0.06666 (9)	0.20926 (8)	0.14912 (6)	0.01563 (12)
C2	−0.00601 (8)	0.26094 (7)	0.06391 (6)	0.01391 (11)
C3	−0.04990 (9)	0.20506 (8)	−0.04397 (6)	0.01656 (12)
H3	−0.1226	0.1295	−0.0705	0.020*
C4	0.01756 (9)	0.26469 (8)	−0.11267 (6)	0.01546 (12)
C5	0.12882 (9)	0.37751 (8)	−0.06979 (6)	0.01465 (11)
H5	0.1754	0.4190	−0.1134	0.018*
C6	0.16685 (8)	0.42490 (7)	0.03947 (5)	0.01292 (11)
C7	0.28988 (9)	0.53963 (8)	0.09859 (6)	0.01487 (11)
C8	0.08025 (9)	0.62575 (7)	0.42266 (6)	0.01421 (11)
C9	0.19209 (8)	0.53834 (7)	0.47982 (5)	0.01287 (11)
C10	0.23152 (9)	0.54827 (8)	0.58878 (6)	0.01447 (11)
H10	0.1879	0.6108	0.6338	0.017*
C11	0.33960 (9)	0.46069 (8)	0.62872 (6)	0.01443 (11)
C12	0.40380 (9)	0.36772 (8)	0.55896 (6)	0.01472 (11)
H12	0.4767	0.3100	0.5843	0.018*
C13	0.35558 (8)	0.36443 (7)	0.45134 (6)	0.01300 (11)
C14	0.41057 (9)	0.26960 (7)	0.36476 (6)	0.01460 (11)
C15	0.42237 (9)	0.18398 (8)	0.03028 (6)	0.01729 (12)
C16	0.20223 (9)	0.02991 (8)	0.46651 (7)	0.01741 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.01507 (5)	0.01471 (4)	0.00908 (4)	0.00167 (3)	0.00287 (3)	0.00302 (3)
O1	0.0216 (3)	0.0205 (2)	0.0116 (2)	−0.0011 (2)	0.00473 (19)	0.00417 (18)
O2	0.0293 (3)	0.0251 (3)	0.0181 (3)	−0.0102 (2)	0.0079 (2)	0.0024 (2)
O3	0.0347 (3)	0.0192 (2)	0.0091 (2)	−0.0019 (2)	0.0017 (2)	0.00284 (18)
O4	0.0263 (3)	0.0261 (3)	0.0201 (3)	−0.0075 (2)	0.0076 (2)	0.0064 (2)
O5	0.0173 (2)	0.0194 (2)	0.0125 (2)	−0.00028 (18)	0.00219 (18)	0.00193 (18)
O6	0.0193 (2)	0.0184 (2)	0.0119 (2)	0.00462 (19)	0.00323 (18)	0.00461 (18)
O7	0.0252 (3)	0.0201 (3)	0.0179 (2)	0.0094 (2)	0.0069 (2)	0.0034 (2)
O8	0.0218 (3)	0.0283 (3)	0.0092 (2)	0.0049 (2)	−0.00023 (19)	0.0026 (2)
O9	0.0243 (3)	0.0229 (3)	0.0208 (3)	0.0117 (2)	0.0086 (2)	0.0079 (2)
O10	0.0230 (3)	0.0196 (2)	0.0121 (2)	0.0061 (2)	0.00636 (19)	0.00398 (18)
O11	0.0262 (3)	0.0188 (2)	0.0177 (2)	0.0029 (2)	0.0082 (2)	0.0044 (2)
O12	0.0487 (5)	0.0521 (6)	0.0417 (5)	−0.0196 (5)	0.0255 (4)	−0.0149 (4)
N1	0.0141 (2)	0.0150 (2)	0.0107 (2)	0.00126 (19)	0.00302 (18)	0.00398 (18)
N2	0.0140 (2)	0.0139 (2)	0.0106 (2)	0.00212 (18)	0.00304 (18)	0.00285 (18)
N3	0.0222 (3)	0.0198 (3)	0.0177 (3)	−0.0040 (2)	0.0059 (2)	−0.0021 (2)
N4	0.0392 (4)	0.0245 (3)	0.0186 (3)	−0.0094 (3)	0.0127 (3)	−0.0046 (3)
N5	0.0268 (3)	0.0208 (3)	0.0212 (3)	−0.0058 (3)	0.0068 (3)	0.0031 (2)
N6	0.0266 (3)	0.0242 (3)	0.0192 (3)	0.0068 (3)	0.0045 (3)	0.0103 (3)
N7	0.0300 (4)	0.0283 (4)	0.0263 (4)	0.0142 (3)	0.0130 (3)	0.0135 (3)
N8	0.0262 (3)	0.0229 (3)	0.0187 (3)	0.0076 (3)	0.0047 (3)	0.0068 (2)
C1	0.0180 (3)	0.0167 (3)	0.0136 (3)	0.0009 (2)	0.0053 (2)	0.0047 (2)
C2	0.0154 (3)	0.0152 (3)	0.0115 (3)	0.0008 (2)	0.0029 (2)	0.0041 (2)
C3	0.0202 (3)	0.0167 (3)	0.0118 (3)	−0.0015 (2)	0.0020 (2)	0.0035 (2)
C4	0.0205 (3)	0.0156 (3)	0.0098 (2)	0.0018 (2)	0.0020 (2)	0.0034 (2)
C5	0.0179 (3)	0.0161 (3)	0.0109 (2)	0.0018 (2)	0.0038 (2)	0.0046 (2)
C6	0.0137 (3)	0.0148 (3)	0.0109 (2)	0.0017 (2)	0.0030 (2)	0.0041 (2)
C7	0.0148 (3)	0.0157 (3)	0.0144 (3)	0.0010 (2)	0.0036 (2)	0.0036 (2)
C8	0.0150 (3)	0.0149 (3)	0.0135 (3)	0.0021 (2)	0.0036 (2)	0.0043 (2)
C9	0.0140 (3)	0.0136 (2)	0.0109 (2)	0.0013 (2)	0.0028 (2)	0.0023 (2)
C10	0.0159 (3)	0.0160 (3)	0.0106 (2)	0.0012 (2)	0.0024 (2)	0.0016 (2)
C11	0.0151 (3)	0.0171 (3)	0.0098 (2)	−0.0002 (2)	0.0010 (2)	0.0023 (2)
C12	0.0154 (3)	0.0163 (3)	0.0122 (3)	0.0022 (2)	0.0016 (2)	0.0040 (2)
C13	0.0140 (3)	0.0137 (3)	0.0117 (2)	0.0017 (2)	0.0033 (2)	0.0032 (2)
C14	0.0168 (3)	0.0146 (3)	0.0140 (3)	0.0027 (2)	0.0059 (2)	0.0039 (2)
C15	0.0180 (3)	0.0152 (3)	0.0180 (3)	0.0007 (2)	0.0051 (2)	0.0011 (2)
C16	0.0171 (3)	0.0176 (3)	0.0197 (3)	0.0023 (2)	0.0051 (2)	0.0082 (2)

Geometric parameters (Å, º) top

Ni1—N2	1.9665 (6)	N4—H4A	0.9000
Ni1—N1	1.9700 (6)	N4—H4B	0.9000
Ni1—O1	2.1088 (6)	N5—C15	1.3267 (11)
Ni1—O10	2.1387 (6)	N5—H5A	0.9002
Ni1—O6	2.1477 (6)	N5—H5B	0.9000
Ni1—O5	2.2149 (6)	N6—C16	1.3394 (10)
O1—C1	1.2668 (9)	N6—H6A	0.9000
O2—C1	1.2492 (10)	N6—H6B	0.9001
O3—C4	1.3394 (9)	N7—C16	1.3247 (11)
O3—H3C	0.9000	N7—H7A	0.9000
O4—C7	1.2357 (9)	N7—H7B	0.8999
O5—C7	1.2895 (9)	N8—C16	1.3238 (11)
O6—C8	1.2880 (9)	N8—H8A	0.9000
O7—C8	1.2343 (10)	N8—H8B	0.9002
O8—C11	1.3485 (9)	C1—C2	1.5198 (10)
O8—H8	0.9000	C2—C3	1.3832 (10)
O9—C14	1.2413 (9)	C3—C4	1.4044 (11)
O10—C14	1.2796 (9)	C3—H3	0.9300
O11—H11A	0.9000	C4—C5	1.4055 (11)
O11—H11B	0.9001	C5—C6	1.3857 (10)
O12—H12B	0.9000	C5—H5	0.9300
O12—H12A	0.9000	C6—C7	1.5111 (10)
N1—C6	1.3371 (9)	C8—C9	1.5141 (10)
N1—C2	1.3374 (9)	C9—C10	1.3856 (10)
N2—C9	1.3363 (9)	C10—C11	1.4032 (11)
N2—C13	1.3368 (9)	C10—H10	0.9300
N3—C15	1.3296 (10)	C11—C12	1.4021 (11)
N3—H3A	0.9001	C12—C13	1.3833 (10)
N3—H3B	0.9001	C12—H12	0.9300
N4—C15	1.3256 (11)	C13—C14	1.5143 (10)

N2—Ni1—N1	171.30 (3)	O2—C1—C2	118.69 (7)
O1—Ni1—O5	154.97 (2)	O1—C1—C2	115.64 (6)
O10—Ni1—O6	154.87 (2)	N1—C2—C3	121.56 (7)
N2—Ni1—O1	96.84 (2)	N1—C2—C1	112.83 (6)
N1—Ni1—O1	78.70 (2)	C3—C2—C1	125.60 (7)
N2—Ni1—O10	77.95 (2)	C2—C3—C4	118.69 (7)
N1—Ni1—O10	94.76 (2)	C2—C3—H3	120.7
O1—Ni1—O10	93.41 (3)	C4—C3—H3	120.7
N2—Ni1—O6	77.41 (2)	O3—C4—C3	118.15 (7)
N1—Ni1—O6	110.20 (2)	O3—C4—C5	122.66 (7)
O1—Ni1—O6	94.31 (2)	C3—C4—C5	119.18 (7)
N2—Ni1—O5	108.19 (2)	C6—C5—C4	117.89 (6)
N1—Ni1—O5	76.46 (2)	C6—C5—H5	121.1
O10—Ni1—O5	91.73 (2)	C4—C5—H5	121.1
O6—Ni1—O5	91.30 (2)	N1—C6—C5	122.25 (7)
C1—O1—Ni1	114.35 (5)	N1—C6—C7	113.16 (6)
C4—O3—H3C	111.0	C5—C6—C7	124.55 (6)
C7—O5—Ni1	113.28 (5)	O4—C7—O5	125.12 (7)
C8—O6—Ni1	114.63 (5)	O4—C7—C6	119.22 (7)
C11—O8—H8	109.2	O5—C7—C6	115.66 (6)
C14—O10—Ni1	114.35 (5)	O7—C8—O6	126.10 (7)
H11A—O11—H11B	109.4	O7—C8—C9	119.17 (7)
H12B—O12—H12A	115.5	O6—C8—C9	114.73 (6)
C6—N1—C2	120.41 (6)	N2—C9—C10	121.93 (7)
C6—N1—Ni1	121.23 (5)	N2—C9—C8	112.93 (6)
C2—N1—Ni1	117.81 (5)	C10—C9—C8	125.14 (7)
C9—N2—C13	120.78 (6)	C9—C10—C11	117.64 (7)
C9—N2—Ni1	119.82 (5)	C9—C10—H10	121.2
C13—N2—Ni1	119.03 (5)	C11—C10—H10	121.2
C15—N3—H3A	119.6	O8—C11—C12	121.73 (7)
C15—N3—H3B	119.6	O8—C11—C10	118.30 (7)
H3A—N3—H3B	120.4	C12—C11—C10	119.96 (6)
C15—N4—H4A	117.6	C13—C12—C11	118.05 (7)
C15—N4—H4B	120.5	C13—C12—H12	121.0
H4A—N4—H4B	121.3	C11—C12—H12	121.0
C15—N5—H5A	115.0	N2—C13—C12	121.62 (7)
C15—N5—H5B	119.8	N2—C13—C14	113.12 (6)
H5A—N5—H5B	125.0	C12—C13—C14	125.25 (7)
C16—N6—H6A	121.8	O9—C14—O10	125.71 (7)
C16—N6—H6B	118.1	O9—C14—C13	119.11 (7)
H6A—N6—H6B	118.4	O10—C14—C13	115.17 (6)
C16—N7—H7A	121.3	N4—C15—N5	120.87 (8)
C16—N7—H7B	116.5	N4—C15—N3	119.19 (8)
H7A—N7—H7B	121.1	N5—C15—N3	119.93 (8)
C16—N8—H8A	116.9	N8—C16—N7	121.25 (8)
C16—N8—H8B	119.8	N8—C16—N6	119.57 (8)
H8A—N8—H8B	121.8	N7—C16—N6	119.16 (8)
O2—C1—O1	125.67 (7)

N2—Ni1—O1—C1	−165.80 (6)	O2—C1—C2—C3	−1.87 (12)
N1—Ni1—O1—C1	6.63 (6)	O1—C1—C2—C3	177.90 (8)
O10—Ni1—O1—C1	−87.54 (6)	N1—C2—C3—C4	−0.79 (12)
O6—Ni1—O1—C1	116.39 (6)	C1—C2—C3—C4	−179.78 (7)
O5—Ni1—O1—C1	13.95 (10)	C2—C3—C4—O3	−179.99 (7)
N2—Ni1—O5—C7	170.16 (5)	C2—C3—C4—C5	0.95 (12)
N1—Ni1—O5—C7	−2.20 (5)	O3—C4—C5—C6	−179.04 (7)
O1—Ni1—O5—C7	−9.58 (9)	C3—C4—C5—C6	−0.02 (11)
O10—Ni1—O5—C7	92.27 (5)	C2—N1—C6—C5	1.36 (11)
O6—Ni1—O5—C7	−112.67 (5)	Ni1—N1—C6—C5	172.68 (5)
N2—Ni1—O6—C8	−2.86 (5)	C2—N1—C6—C7	−176.55 (6)
N1—Ni1—O6—C8	172.73 (5)	Ni1—N1—C6—C7	−5.23 (8)
O1—Ni1—O6—C8	93.20 (5)	C4—C5—C6—N1	−1.14 (11)
O10—Ni1—O6—C8	−14.34 (9)	C4—C5—C6—C7	176.52 (7)
O5—Ni1—O6—C8	−111.22 (5)	Ni1—O5—C7—O4	−179.06 (7)
N2—Ni1—O10—C14	3.50 (5)	Ni1—O5—C7—C6	0.27 (8)
N1—Ni1—O10—C14	−171.70 (6)	N1—C6—C7—O4	−177.72 (7)
O1—Ni1—O10—C14	−92.77 (6)	C5—C6—C7—O4	4.43 (12)
O6—Ni1—O10—C14	14.95 (9)	N1—C6—C7—O5	2.91 (10)
O5—Ni1—O10—C14	111.74 (6)	C5—C6—C7—O5	−174.94 (7)
N2—Ni1—N1—C6	−119.19 (16)	Ni1—O6—C8—O7	179.06 (7)
O1—Ni1—N1—C6	−179.02 (6)	Ni1—O6—C8—C9	−0.37 (8)
O10—Ni1—N1—C6	−86.48 (6)	C13—N2—C9—C10	−0.51 (11)
O6—Ni1—N1—C6	90.51 (6)	Ni1—N2—C9—C10	172.42 (5)
O5—Ni1—N1—C6	4.16 (6)	C13—N2—C9—C8	178.98 (6)
N2—Ni1—N1—C2	52.35 (19)	Ni1—N2—C9—C8	−8.09 (8)
O1—Ni1—N1—C2	−7.48 (6)	O7—C8—C9—N2	−174.29 (7)
O10—Ni1—N1—C2	85.06 (6)	O6—C8—C9—N2	5.18 (9)
O6—Ni1—N1—C2	−97.95 (6)	O7—C8—C9—C10	5.17 (11)
O5—Ni1—N1—C2	175.70 (6)	O6—C8—C9—C10	−175.36 (7)
N1—Ni1—N2—C9	−145.37 (15)	N2—C9—C10—C11	0.58 (11)
O1—Ni1—N2—C9	−86.74 (6)	C8—C9—C10—C11	−178.84 (7)
O10—Ni1—N2—C9	−178.78 (6)	C9—C10—C11—O8	−179.59 (7)
O6—Ni1—N2—C9	6.18 (5)	C9—C10—C11—C12	0.16 (11)
O5—Ni1—N2—C9	93.38 (6)	O8—C11—C12—C13	178.81 (7)
N1—Ni1—N2—C13	27.7 (2)	C10—C11—C12—C13	−0.94 (11)
O1—Ni1—N2—C13	86.32 (6)	C9—N2—C13—C12	−0.33 (11)
O10—Ni1—N2—C13	−5.72 (5)	Ni1—N2—C13—C12	−173.32 (5)
O6—Ni1—N2—C13	179.23 (6)	C9—N2—C13—C14	179.79 (6)
O5—Ni1—N2—C13	−93.57 (6)	Ni1—N2—C13—C14	6.80 (8)
Ni1—O1—C1—O2	174.96 (7)	C11—C12—C13—N2	1.04 (11)
Ni1—O1—C1—C2	−4.79 (9)	C11—C12—C13—C14	−179.09 (7)
C6—N1—C2—C3	−0.36 (11)	Ni1—O10—C14—O9	−179.76 (7)
Ni1—N1—C2—C3	−171.97 (6)	Ni1—O10—C14—C13	−1.05 (8)
C6—N1—C2—C1	178.76 (6)	N2—C13—C14—O9	175.34 (7)
Ni1—N1—C2—C1	7.15 (8)	C12—C13—C14—O9	−4.54 (11)
O2—C1—C2—N1	179.06 (7)	N2—C13—C14—O10	−3.46 (9)
O1—C1—C2—N1	−1.17 (10)	C12—C13—C14—O10	176.66 (7)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3C···O6ⁱ	0.90	1.71	2.5901 (8)	166
O8—H8···O5ⁱⁱ	0.90	1.84	2.7057 (9)	160
O11—H11A···O9ⁱⁱⁱ	0.90	1.86	2.7106 (9)	156
O11—H11B···O2^iv	0.90	1.88	2.7464 (9)	161
O12—H12B···O11ⁱⁱ	0.90	2.15	3.0425 (12)	172
O12—H12A···O5	0.90	2.15	3.0244 (13)	164
O12—H12A···O4	0.90	2.64	3.3823 (12)	141
N3—H3A···O4^v	0.90	2.15	2.9307 (10)	144
N3—H3B···O10	0.90	2.07	2.8817 (10)	149
N4—H4A···O4^v	0.90	1.97	2.8072 (11)	154
N4—H4B···O11^vi	0.90	2.06	2.9161 (10)	159
N5—H5A···O10	0.90	2.19	2.9887 (10)	148
N5—H5B···O2^vii	0.90	1.98	2.8656 (10)	169
N6—H6A···O7^viii	0.90	2.28	3.0178 (11)	139
N6—H6A···O1	0.90	2.49	3.0038 (9)	117
N6—H6B···O3^vii	0.90	2.55	3.2320 (11)	133
N7—H7A···O9ⁱⁱⁱ	0.90	2.01	2.8999 (10)	172
N7—H7B···O12^ix	0.90	1.93	2.8282 (13)	176
N8—H8A···O7^viii	0.90	1.94	2.7993 (10)	158
N8—H8B···O11	0.90	1.99	2.8847 (10)	174
N5—H5A···Cg1(N1/C2–C6)	0.90	3.47	3.362 (7)	75

Symmetry codes: (i) −x, −y+1, −z; (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+1; (iv) −x, −y, −z+1; (v) −x+1, −y+1, −z; (vi) x, y, z−1; (vii) −x, −y, −z; (viii) −x, −y+1, −z+1; (ix) x, y−1, z.

Experimental details

Crystal data
Chemical formula	(CH₆N₃)₂[Ni(C₇H₃NO₅)₂]·2H₂O
M_r	577.13
Crystal system, space group	Triclinic, P1
Temperature (K)	150
a, b, c (Å)	8.9253 (6), 9.9060 (6), 13.2186 (9)
α, β, γ (°)	101.415 (3), 103.099 (3), 91.938 (3)
V (Å³)	1111.99 (13)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.96
Crystal size (mm)	0.50 × 0.32 × 0.15

Data collection
Diffractometer	Bruker SMART 1000
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.647, 0.870
No. of measured, independent and observed [I > 2σ(I)] reflections	46516, 10497, 9650
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.834

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.076, 1.06
No. of reflections	10497
No. of parameters	334
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.56, −0.61

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2005) and Mercury (Version 1.4.2; Macrae et al., 2006).

Selected geometric parameters (Å, º) top

Ni1—N2	1.9665 (6)	Ni1—O10	2.1387 (6)
Ni1—N1	1.9700 (6)	Ni1—O6	2.1477 (6)
Ni1—O1	2.1088 (6)	Ni1—O5	2.2149 (6)

N2—Ni1—N1	171.30 (3)	O1—Ni1—O10	93.41 (3)
O1—Ni1—O5	154.97 (2)	O6—Ni1—O5	91.30 (2)
O10—Ni1—O6	154.87 (2)

O10—Ni1—O5—C7	92.27 (5)	O1—Ni1—O6—C8	93.20 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3C···O6ⁱ	0.90	1.71	2.5901 (8)	165.9
O8—H8···O5ⁱⁱ	0.90	1.84	2.7057 (9)	159.7
O11—H11A···O9ⁱⁱⁱ	0.90	1.86	2.7106 (9)	156.0
O11—H11B···O2^iv	0.90	1.88	2.7464 (9)	161.3
O12—H12B···O11ⁱⁱ	0.90	2.15	3.0425 (12)	171.9
O12—H12A···O5	0.90	2.15	3.0244 (13)	164.0
O12—H12A···O4	0.90	2.64	3.3823 (12)	141.0
N3—H3A···O4^v	0.90	2.15	2.9307 (10)	143.9
N3—H3B···O10	0.90	2.07	2.8817 (10)	149.0
N4—H4A···O4^v	0.90	1.97	2.8072 (11)	154.0
N4—H4B···O11^vi	0.90	2.06	2.9161 (10)	159.3
N5—H5A···O10	0.90	2.19	2.9887 (10)	147.7
N5—H5B···O2^vii	0.90	1.98	2.8656 (10)	169.0
N6—H6A···O7^viii	0.90	2.28	3.0178 (11)	138.6
N6—H6A···O1	0.90	2.49	3.0038 (9)	116.7
N6—H6B···O3^vii	0.90	2.55	3.2320 (11)	132.8
N7—H7A···O9ⁱⁱⁱ	0.90	2.01	2.8999 (10)	171.6
N7—H7B···O12^ix	0.90	1.93	2.8282 (13)	176.2
N8—H8A···O7^viii	0.90	1.94	2.7993 (10)	157.9
N8—H8B···O11	0.90	1.99	2.8847 (10)	174.2
N5—H5A···Cg1(N1/C2–C6)	0.90	3.47	3.362 (7)	75.3

Acknowledgements

Financial support from Ilam University and the Teacher Training University, Tehran, is gratefully acknowledged.

References

Aghabozorg, H., Attar Gharamaleki, J., Ghadermazi, M., Ghasemikhah, P. & Soleimannejad, J. (2007a). Acta Cryst. E63, m1803–m1804. Web of Science CSD CrossRef IUCr Journals Google Scholar
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