Poly[[hemi-μ4-oxalato-hemi-μ2-oxalato-bis­(μ3-pyrazine-2-carboxyl­ato)erbium(III)silver(I)] monohydrate]

Zhao, L.-Z.; He, R.-X.; Zhong, Q.-G.; Zeng, R.-H.; Lu, D.-S.

doi:10.1107/S1600536809029742

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Pages m1018-m1019

doi:10.1107/S1600536809029742

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Poly[[hemi-μ₄-oxalato-hemi-μ₂-oxalato-bis(μ₃-pyrazine-2-carboxylato)erbium(III)silver(I)] monohydrate]

Ling-Zhi Zhao,^a,^b Rui-Xia He,^a Qiu-Gui Zhong,^a Rong-Hua Zeng ^a,^b ^* and Dong-Sheng Lu ^a,^b

^aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China, and ^bKey Laboratory of the Technology of Electrochemical Energy Storage and Power Generation in Guangdong Universities, South China Normal University, Guangzhou 510006, People's Republic of China
^*Correspondence e-mail: zrh321@yahoo.com.cn

(Received 21 June 2009; accepted 27 July 2009; online 31 July 2009)

The asymmetric unit of the title complex, {[AgEr(C₅H₃N₂O₂)₂(C₂O₄)]·H₂O}_n, contains one Er^III atom, one Ag^I atom, two pyrazine-2-carboxylate (pyc) ligands, two half oxalate ligands (each lying on an inversion center) and one uncoordinated water molecule. The Er^III atom is coordinated by two O atoms and two N atoms from two pyc ligands, one O atom from a third pyc ligand and four O atoms from two oxalate ligands in a distorted monocapped square-antiprismatic geometry. The Ag^I atom is coordinated by two N atoms from two pyc ligands, one O atom from a third pyc ligand and one O atom from one oxalate ligand. The crystal structure exhibits a three-dimensional heterometallic polymeric network. O—H⋯O hydrogen bonding between the uncoordinated water molecule and carboxylate O atoms is observed.

Related literature

For general background to lanthanide–transition heterometallic complexes, see: Deng et al. (2008 ); Wang et al. (2006 ); Zhou et al. (2006 ).

Experimental

Crystal data

[AgEr(C₅H₃N₂O₂)₂(C₂O₄)]·H₂O
M_r = 627.35
Monoclinic, P 2₁ /c
a = 10.0482 (6) Å
b = 18.3968 (11) Å
c = 8.0371 (5) Å
β = 95.397 (1)°
V = 1479.11 (16) Å³
Z = 4
Mo Kα radiation
μ = 7.02 mm⁻¹
T = 296 K
0.22 × 0.20 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.307, T_max = 0.349 (expected range = 0.232–0.263)
7533 measured reflections
2649 independent reflections
2450 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.050
S = 1.04
2649 reflections
244 parameters
12 restraints
H-atom parameters constrained
Δρ_max = 1.43 e Å⁻³
Δρ_min = −1.14 e Å⁻³

Table 1
Selected bond lengths (Å)

Er1—O4	2.333 (3)
Er1—O7	2.367 (3)
Er1—O1	2.385 (3)
Er1—O6ⁱ	2.387 (3)
Er1—O8ⁱⁱ	2.388 (3)
Er1—O2ⁱⁱⁱ	2.403 (3)
Er1—O5	2.451 (3)
Er1—N1	2.611 (4)
Er1—N3	2.636 (4)
Ag1—N4^iv	2.299 (4)
Ag1—O3^v	2.312 (3)
Ag1—N2	2.368 (4)
Ag1—O5^vi	2.648 (4)
Symmetry codes: (i) -x+1, -y, -z; (ii) -x+1, -y, -z+1; (iii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[x+1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (v) $[x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (vi) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W⋯O1	0.86	2.14	2.971 (6)	162

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809029742/hy2207sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809029742/hy2207Isup2.hkl

checkCIF report

Comment top

In recent years, many research groups have devoted their work to the design and synthesis of lanthanide–transition heterometallic coordination frameworks with bridging multifunctional organic ligands, not only because of their fascinating topological networks but also due to their potential applications in ion exchange, gas storage, catalysis and luminescence (Wang et al., 2006; Zhou et al., 2006). As a building block, pyrazine-2-carboxylate (pyc) and oxalate are excellent candidates for the construction of heterometallic complexes (Deng et al., 2008). Recently, we obtained the title coordination polymer, which was synthesized under hydrothermal conditions.

The asymmetric unit of the title complex contains one Er^III atom, one Ag^I atom, two pyc ligands, two half oxalate ligands, each lying on an inversion center, and one uncoordinated water molecule (Fig. 1). The Er^III atom is coordinated by two O atoms and two N atoms from two pyc ligands, one O atom from a third pyc ligand and four O atoms from two oxalate ligands. The coordination geometry around the Er^III atom can be described as distorted monocapped square-antiprismatic, with Er—O bond distances and O—Er—O bond angles range from 2.333 (3) to 2.451 (3) Å and 66.24 (9) to 147.36 (10)°, respectively (Table 1). The Ag^I atom has a distorted tetrahedral coordination geometry, defined by two N atoms from two pyc ligands, one O atom from a third pyc ligand and one O atom from one oxalate ligand. The Ag—N and Ag—O bond distances vary from 2.299 (4) to 2.648 (4) Å. The oxalate ligands bridge the Er atoms to form a zigzag chain. These chains are further interconnected by Ag–pyc subunits into a three-dimensional polymeric network (Fig. 2). O—H···O hydrogen bond involving the carboxylate O atoms of the pyc ligands and uncoordinated water molecules further enhance the stability of the three-dimensional network (Table 2).

Related literature top

For general background to lanthanide–transition heterometallic complexes, see: Deng et al. (2008); Wang et al. (2006); Zhou et al. (2006).

Experimental top

A mixture of Er₂O₃ (0.183 g, 0.5 mmol), AgNO₃ (0.170 g, 1 mmol), pyrazine-2-carboxylic acid (0.124 g, 1 mmol), oxalic acid (0.09 g, 1 mmol) and water (10 ml) in the presence of HNO₃ (0.024 g, 0.385 mmol) was stirred vigorously for 20 min and then sealed in a Teflon-lined stainless steel autoclave (20 ml capacity). The autoclave was heated and maintained at 433 K for 3 d, and then cooled to room temperature at 5 K h^-1. Colorless block crystals were obtained.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The asymmetric unit of the title compound. H atoms have been omitted for clarity. [Symmetry codes: (i) 1-x, -y, -z; (ii) 1-x, -y, 1-z; (iii) x, 1/2-y, -1/2+z; (iv) 1+x, 1/2-y, -1/2+z; (v) 1+x, 1/2-y, 1/2+z; (vi) 1-x, 1/2+y, 1/2-z.]
	Fig. 2. Packing diagram of the title compound.

Poly[[hemi-µ₄-oxalato-hemi-µ₂-oxalato-bis(µ₃-pyrazine-2- carboxylato)erbium(III)silver(I)] monohydrate] top

Crystal data top

[AgEr(C₅H₃N₂O₂)₂(C₂O₄)]·H₂O	F(000) = 1180
M_r = 627.35	D_x = 2.817 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5128 reflections
a = 10.0482 (6) Å	θ = 2.2–28.2°
b = 18.3968 (11) Å	µ = 7.02 mm⁻¹
c = 8.0371 (5) Å	T = 296 K
β = 95.397 (1)°	Block, colorless
V = 1479.11 (16) Å³	0.22 × 0.20 × 0.19 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	2649 independent reflections
Radiation source: fine-focus sealed tube	2450 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
ϕ and ω scans	θ_max = 25.2°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −11→12
T_min = 0.307, T_max = 0.349	k = −22→19
7533 measured reflections	l = −9→5

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)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.050	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.024P)² + 4.153P] where P = (F_o² + 2F_c²)/3
2649 reflections	(Δ/σ)_max = 0.001
244 parameters	Δρ_max = 1.43 e Å⁻³
12 restraints	Δρ_min = −1.14 e Å⁻³

Crystal data top

[AgEr(C₅H₃N₂O₂)₂(C₂O₄)]·H₂O	V = 1479.11 (16) Å³
M_r = 627.35	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.0482 (6) Å	µ = 7.02 mm⁻¹
b = 18.3968 (11) Å	T = 296 K
c = 8.0371 (5) Å	0.22 × 0.20 × 0.19 mm
β = 95.397 (1)°

Data collection top

Bruker APEXII CCD diffractometer	2649 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2450 reflections with I > 2σ(I)
T_min = 0.307, T_max = 0.349	R_int = 0.019
7533 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	12 restraints
wR(F²) = 0.050	H-atom parameters constrained
S = 1.04	Δρ_max = 1.43 e Å⁻³
2649 reflections	Δρ_min = −1.14 e Å⁻³
244 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Er1	0.364162 (17)	0.105359 (10)	0.24162 (2)	0.01442 (7)
Ag1	0.85087 (4)	0.42746 (2)	0.39306 (4)	0.03045 (11)
O1	0.2989 (3)	0.21768 (16)	0.3579 (4)	0.0242 (7)
O2	0.3493 (3)	0.32200 (16)	0.4921 (4)	0.0235 (7)
O3	−0.0813 (3)	0.0887 (2)	0.1736 (4)	0.0317 (8)
O4	0.1381 (3)	0.09487 (18)	0.1482 (4)	0.0250 (7)
O5	0.3318 (3)	0.01811 (16)	0.0110 (4)	0.0207 (6)
O7	0.5023 (3)	0.09455 (15)	0.4957 (4)	0.0199 (6)
N1	0.5506 (3)	0.20455 (19)	0.2760 (4)	0.0190 (8)
N2	0.7204 (4)	0.3245 (2)	0.3075 (5)	0.0289 (9)
N3	0.1969 (4)	0.09160 (19)	0.4735 (4)	0.0194 (8)
N4	−0.0028 (4)	0.0827 (2)	0.6909 (4)	0.0239 (8)
C1	0.3752 (4)	0.2695 (2)	0.4013 (5)	0.0193 (9)
C2	0.5118 (4)	0.2678 (2)	0.3374 (5)	0.0195 (9)
C3	0.5950 (4)	0.3270 (3)	0.3465 (6)	0.0259 (10)
H3	0.5621	0.3711	0.3818	0.031*
C4	0.7614 (5)	0.2604 (3)	0.2544 (6)	0.0287 (11)
H4	0.8491	0.2554	0.2282	0.034*
C5	0.6765 (4)	0.2009 (3)	0.2372 (6)	0.0255 (10)
H5	0.7082	0.1573	0.1976	0.031*
C6	0.0371 (4)	0.0914 (2)	0.2309 (5)	0.0185 (9)
C7	0.0668 (4)	0.0902 (2)	0.4181 (5)	0.0183 (9)
C8	−0.0327 (4)	0.0862 (3)	0.5258 (5)	0.0223 (10)
H8	−0.1219	0.0860	0.4824	0.027*
C9	0.1265 (4)	0.0855 (3)	0.7468 (5)	0.0267 (10)
H9	0.1508	0.0845	0.8614	0.032*
C10	0.2255 (4)	0.0900 (3)	0.6381 (6)	0.0269 (10)
H10	0.3145	0.0920	0.6818	0.032*
C11	0.4313 (4)	−0.0108 (2)	−0.0429 (5)	0.0164 (9)
C12	0.5388 (4)	0.0323 (2)	0.5434 (5)	0.0176 (9)
O1W	0.0424 (5)	0.2589 (3)	0.4885 (8)	0.0827 (16)
H1W	0.1096	0.2521	0.4314	0.124*
H2W	0.0662	0.2368	0.5816	0.124*
O6	0.4323 (3)	−0.05626 (16)	−0.1587 (4)	0.0212 (7)
O8	0.6284 (3)	0.01649 (16)	0.6555 (4)	0.0226 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Er1	0.01594 (11)	0.01469 (11)	0.01268 (11)	0.00069 (7)	0.00162 (7)	−0.00034 (7)
Ag1	0.0286 (2)	0.0423 (2)	0.02146 (19)	−0.00868 (16)	0.00783 (14)	−0.00439 (16)
O1	0.0201 (15)	0.0210 (16)	0.0326 (18)	−0.0023 (13)	0.0074 (13)	−0.0060 (14)
O2	0.0281 (17)	0.0210 (16)	0.0212 (16)	0.0042 (13)	0.0014 (13)	−0.0076 (13)
O3	0.0201 (16)	0.059 (2)	0.0152 (16)	0.0027 (15)	−0.0017 (13)	−0.0041 (15)
O4	0.0199 (16)	0.042 (2)	0.0140 (15)	−0.0004 (13)	0.0046 (12)	0.0007 (14)
O5	0.0205 (15)	0.0238 (17)	0.0176 (15)	0.0042 (13)	0.0006 (12)	−0.0029 (13)
O7	0.0255 (16)	0.0166 (15)	0.0169 (15)	0.0009 (12)	−0.0013 (12)	0.0016 (12)
N1	0.0229 (19)	0.0172 (18)	0.0170 (18)	0.0012 (14)	0.0025 (14)	−0.0010 (15)
N2	0.027 (2)	0.028 (2)	0.032 (2)	−0.0040 (17)	0.0074 (17)	−0.0054 (18)
N3	0.0221 (19)	0.0197 (19)	0.0165 (19)	−0.0003 (15)	0.0029 (14)	0.0004 (15)
N4	0.025 (2)	0.032 (2)	0.0160 (19)	0.0015 (16)	0.0052 (15)	0.0012 (16)
C1	0.025 (2)	0.019 (2)	0.013 (2)	0.0028 (18)	0.0001 (17)	0.0025 (18)
C2	0.025 (2)	0.018 (2)	0.015 (2)	0.0029 (17)	0.0000 (17)	0.0000 (17)
C3	0.027 (2)	0.020 (2)	0.031 (3)	−0.0018 (19)	0.0060 (19)	−0.008 (2)
C4	0.020 (2)	0.031 (3)	0.035 (3)	−0.0030 (19)	0.006 (2)	−0.004 (2)
C5	0.022 (2)	0.026 (2)	0.028 (2)	0.0039 (19)	0.0025 (19)	−0.006 (2)
C6	0.021 (2)	0.018 (2)	0.016 (2)	0.0029 (17)	0.0032 (17)	0.0011 (17)
C7	0.020 (2)	0.018 (2)	0.017 (2)	−0.0001 (17)	0.0016 (17)	0.0000 (17)
C8	0.019 (2)	0.032 (3)	0.016 (2)	0.0006 (19)	0.0033 (17)	0.0000 (19)
C9	0.028 (3)	0.039 (3)	0.013 (2)	0.006 (2)	0.0032 (18)	0.004 (2)
C10	0.019 (2)	0.044 (3)	0.018 (2)	0.001 (2)	0.0023 (18)	0.000 (2)
C11	0.023 (2)	0.013 (2)	0.013 (2)	0.0026 (16)	0.0016 (17)	0.0050 (17)
C12	0.019 (2)	0.021 (2)	0.013 (2)	0.0000 (17)	0.0041 (16)	0.0021 (17)
O1W	0.053 (3)	0.067 (3)	0.130 (5)	−0.008 (2)	0.013 (3)	−0.020 (3)
O6	0.0200 (15)	0.0215 (16)	0.0224 (16)	−0.0006 (12)	0.0033 (12)	−0.0073 (13)
O8	0.0237 (16)	0.0220 (16)	0.0209 (16)	−0.0013 (13)	−0.0038 (13)	0.0024 (13)

Geometric parameters (Å, º) top

Er1—O4	2.333 (3)	N3—C10	1.328 (6)
Er1—O7	2.367 (3)	N3—C7	1.341 (5)
Er1—O1	2.385 (3)	N4—C8	1.335 (5)
Er1—O6ⁱ	2.387 (3)	N4—C9	1.336 (6)
Er1—O8ⁱⁱ	2.388 (3)	C1—C2	1.510 (6)
Er1—O2ⁱⁱⁱ	2.403 (3)	C2—C3	1.370 (6)
Er1—O5	2.451 (3)	C3—H3	0.9300
Er1—N1	2.611 (4)	C4—C5	1.387 (7)
Er1—N3	2.636 (4)	C4—H4	0.9300
Ag1—N4^iv	2.299 (4)	C5—H5	0.9300
Ag1—O3^v	2.312 (3)	C6—C7	1.506 (6)
Ag1—N2	2.368 (4)	C7—C8	1.385 (6)
Ag1—O5^vi	2.648 (4)	C8—H8	0.9300
O1—C1	1.253 (5)	C9—C10	1.387 (6)
O2—C1	1.252 (5)	C9—H9	0.9300
O3—C6	1.236 (5)	C10—H10	0.9300
O4—C6	1.265 (5)	C11—O6	1.252 (5)
O5—C11	1.245 (5)	C11—C11ⁱ	1.537 (8)
O7—C12	1.252 (5)	C12—O8	1.247 (5)
N1—C5	1.332 (6)	C12—C12ⁱⁱ	1.549 (8)
N1—C2	1.337 (5)	O1W—H1W	0.86
N2—C3	1.328 (6)	O1W—H2W	0.86
N2—C4	1.332 (6)

O4—Er1—O7	138.16 (10)	C3—N2—C4	115.8 (4)
O4—Er1—O1	84.40 (11)	C3—N2—Ag1	114.5 (3)
O7—Er1—O1	83.98 (10)	C4—N2—Ag1	128.4 (3)
O4—Er1—O6ⁱ	135.46 (10)	C10—N3—C7	116.3 (4)
O7—Er1—O6ⁱ	76.17 (10)	C10—N3—Er1	127.9 (3)
O1—Er1—O6ⁱ	135.36 (10)	C7—N3—Er1	115.7 (3)
O4—Er1—O8ⁱⁱ	91.81 (11)	C8—N4—C9	117.0 (4)
O7—Er1—O8ⁱⁱ	68.02 (10)	C8—N4—Ag1^ix	127.4 (3)
O1—Er1—O8ⁱⁱ	132.72 (11)	C9—N4—Ag1^ix	115.6 (3)
O6ⁱ—Er1—O8ⁱⁱ	75.03 (10)	O2—C1—O1	126.4 (4)
O4—Er1—O2ⁱⁱⁱ	78.18 (10)	O2—C1—C2	117.4 (4)
O7—Er1—O2ⁱⁱⁱ	138.78 (10)	O1—C1—C2	116.2 (4)
O1—Er1—O2ⁱⁱⁱ	81.23 (11)	N1—C2—C3	120.9 (4)
O6ⁱ—Er1—O2ⁱⁱⁱ	87.99 (10)	N1—C2—C1	116.7 (4)
O8ⁱⁱ—Er1—O2ⁱⁱⁱ	143.95 (10)	C3—C2—C1	122.3 (4)
O4—Er1—O5	69.30 (10)	N2—C3—C2	123.2 (4)
O7—Er1—O5	128.53 (10)	N2—C3—H3	118.4
O1—Er1—O5	147.36 (10)	C2—C3—H3	118.4
O6ⁱ—Er1—O5	66.24 (9)	N2—C4—C5	121.7 (4)
O8ⁱⁱ—Er1—O5	69.19 (10)	N2—C4—H4	119.2
O2ⁱⁱⁱ—Er1—O5	74.90 (10)	C5—C4—H4	119.2
O4—Er1—N1	139.39 (11)	N1—C5—C4	121.7 (4)
O7—Er1—N1	67.09 (10)	N1—C5—H5	119.1
O1—Er1—N1	64.79 (10)	C4—C5—H5	119.1
O6ⁱ—Er1—N1	70.67 (10)	O3—C6—O4	126.7 (4)
O8ⁱⁱ—Er1—N1	128.36 (10)	O3—C6—C7	117.7 (4)
O2ⁱⁱⁱ—Er1—N1	71.78 (10)	O4—C6—C7	115.6 (4)
O5—Er1—N1	125.49 (10)	N3—C7—C8	122.2 (4)
O4—Er1—N3	63.46 (10)	N3—C7—C6	115.2 (4)
O7—Er1—N3	75.12 (11)	C8—C7—C6	122.6 (4)
O1—Er1—N3	65.75 (11)	N4—C8—C7	121.0 (4)
O6ⁱ—Er1—N3	141.34 (11)	N4—C8—H8	119.5
O8ⁱⁱ—Er1—N3	70.51 (11)	C7—C8—H8	119.5
O2ⁱⁱⁱ—Er1—N3	130.51 (11)	N4—C9—C10	121.6 (4)
O5—Er1—N3	115.07 (10)	N4—C9—H9	119.2
N1—Er1—N3	119.41 (11)	C10—C9—H9	119.2
N4^iv—Ag1—O3^v	121.94 (12)	N3—C10—C9	121.9 (4)
N4^iv—Ag1—N2	95.91 (13)	N3—C10—H10	119.0
O3^v—Ag1—N2	106.55 (13)	C9—C10—H10	119.0
C1—O1—Er1	125.8 (3)	O5—C11—O6	127.3 (4)
C1—O2—Er1^vii	156.2 (3)	O5—C11—C11ⁱ	116.8 (4)
C6—O3—Ag1^viii	123.6 (3)	O6—C11—C11ⁱ	115.9 (4)
C6—O4—Er1	129.8 (3)	O8—C12—O7	127.2 (4)
C11—O5—Er1	119.3 (3)	O8—C12—C12ⁱⁱ	116.4 (5)
C12—O7—Er1	118.2 (3)	O7—C12—C12ⁱⁱ	116.3 (4)
C5—N1—C2	116.5 (4)	H1W—O1W—H2W	103.0
C5—N1—Er1	128.9 (3)	C11—O6—Er1ⁱ	121.8 (3)
C2—N1—Er1	114.6 (3)	C12—O8—Er1ⁱⁱ	117.8 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O1	0.86	2.14	2.971 (6)	162

Experimental details

Crystal data
Chemical formula	[AgEr(C₅H₃N₂O₂)₂(C₂O₄)]·H₂O
M_r	627.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	10.0482 (6), 18.3968 (11), 8.0371 (5)
β (°)	95.397 (1)
V (Å³)	1479.11 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.02
Crystal size (mm)	0.22 × 0.20 × 0.19

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.307, 0.349
No. of measured, independent and observed [I > 2σ(I)] reflections	7533, 2649, 2450
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.050, 1.04
No. of reflections	2649
No. of parameters	244
No. of restraints	12
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.43, −1.14

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Er1—O4	2.333 (3)	Er1—N1	2.611 (4)
Er1—O7	2.367 (3)	Er1—N3	2.636 (4)
Er1—O1	2.385 (3)	Ag1—N4^iv	2.299 (4)
Er1—O6ⁱ	2.387 (3)	Ag1—O3^v	2.312 (3)
Er1—O8ⁱⁱ	2.388 (3)	Ag1—N2	2.368 (4)
Er1—O2ⁱⁱⁱ	2.403 (3)	Ag1—O5^vi	2.648 (4)
Er1—O5	2.451 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O1	0.86	2.14	2.971 (6)	162

Acknowledgements

The authors acknowledge China Postdoctoral Science Foundation (project No. 20080440764), Guangdong Province Natural Science Foundation (project No. 9451063101002082), the Key Laboratory of the Technology of Electrochemical Energy Storage and Power Generation in Guangdong Universities for supporting this work, and also the Young Teacher Training Plan of Guangdong Universities.

References

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