(6-Oxido-2-oxo-1,2-dihydropyrimidine-5-carboxylato-κ2O5,O6)(4-oxido-2-oxo-1,2-dihydropyrimidin-3-ium-5-carboxyl­ato-κ2O4,O5)bis(1,10-phenanthroline-κ2N,N′)erbium(III) dihydrate

Xing, H.-H.; Chen, Z.-L.; Ng, S.W.

doi:10.1107/S1600536808001487

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Page m418

doi:10.1107/S1600536808001487

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(6-Oxido-2-oxo-1,2-dihydropyrimidine-5-carboxylato-κ²O⁵,O⁶)(4-oxido-2-oxo-1,2-dihydropyrimidin-3-ium-5-carboxylato-κ²O⁴,O⁵)bis(1,10-phenanthroline-κ²N,N′)erbium(III) dihydrate

Hui-Hui Xing,^a Zi-Lu Chen ^a and Seik Weng Ng ^b ^*

^aCollege of Chemistry and Chemical Engineering, Guangxi Normal University, Gulin 541004, People's Republic of China, and ^bDepartment of Chemistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 7 January 2008; accepted 15 January 2008; online 25 January 2008)

The erbium(III) atom in the title compound, [Er(C₅H₂N₂O₄)(C₅H₃N₂O₄)(C₁₂H₈N₂)₂]·2H₂O, is located on a twofold rotation axis and chelated by two 1,10-phenanthroline heterocycles as well as by a 2,4-dihydroxypyrimidine-5-carboxylate monoanion and a 2,4-dihydroxypyrimidine-5-carboxylate dianion in a square-antiprismatic coordination geometry.

Related literature

For the structure of 2,4-dihydroxypyridimine-5-carboxylic acid, see: Law et al. (2004 ). This erbium compound is isostructural with the europium, terbium and ytterbium analogs; see Sun & Jin (2004 ) for their detailed description.

Experimental

Crystal data

[Er(C₅H₂N₂O₄)(C₅H₃N₂O₄)(C₁₂H₈N₂)₂]·2H₂O
M_r = 872.88
Monoclinic, C 2/c
a = 17.1602 (7) Å
b = 14.4170 (6) Å
c = 13.2433 (5) Å
β = 101.159 (1)°
V = 3214.4 (2) Å³
Z = 4
Mo Kα radiation
μ = 2.69 mm⁻¹
T = 295 (2) K
0.18 × 0.10 × 0.08 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.645, T_max = 0.814
13567 measured reflections
3680 independent reflections
3495 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.024
wR(F²) = 0.061
S = 1.05
3680 reflections
240 parameters
H-atom parameters constrained
Δρ_max = 1.13 e Å⁻³
Δρ_min = −0.38 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Er1—O2	2.297 (2)
Er1—O3	2.238 (2)
Er1—N3	2.558 (2)
Er1—N4	2.538 (2)

O2—Er1—O2ⁱ	146.6 (1)
O2—Er1—O3	74.8 (1)
O2—Er1—O3ⁱ	81.6 (1)
O2—Er1—N3	74.5 (1)
O2—Er1—N3ⁱ	122.3 (1)
O2—Er1—N4	135.5 (1)
O2—Er1—N4ⁱ	74.6 (1)
O3—Er1—O3ⁱ	89.2 (1)
O3—Er1—N3	148.4 (1)
O3—Er1—N3ⁱ	79.0 (1)
O3—Er1—N4	147.2 (1)
O3—Er1—N4ⁱ	105.5 (1)
N3—Er1—N3ⁱ	124.7 (1)
N3—Er1—N4	64.4 (1)
N3—Er1—N4ⁱ	73.2 (1)
N4—Er1—N4ⁱ	77.9 (1)
Symmetry code: (i) $[-x+1, y, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; method used to solve structure: atomic coordinates taken from published analogs (Sun & Jin, 2004); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808001487/xu2400sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808001487/xu2400Isup2.hkl

checkCIF report

Comment top

2,4-Dihydroxypyrimidine-5-carboxylic acid (uracil-5-carboxylic acid, isoorotic acid) in the form of the singly-, doubly- and triply-deprotonated ion furnishes a number of compounds with both main group and transition metals in which the anion functions in a variety of binding modes. The acid itself exists as hydrated molecules held together by extensive hydrogen bonds (Law et al., 2004). The anion typically uses the 5-carboxylate and the 4-oxo/hydroxy oxygen atoms to chelate as this furnishes a six-membered chelate ring that confers stability.

The 1,10-phenanthroline-chelated rare-earth compounds, Ln(C₁₂H₈N₂)₂(C₅H₃N₂O₄)(C₅H₂N₂O₄)^.2H₂O (Ln = Eu, Tb and Yb) represent the first examples of mononuclear lanthanum derivatives of the acid (Sun & Jin, 2004). The present erbium analog is isostructural with these, whose structures have been described in detail.

Related literature top

For the structure of 2,4-dihydroxypyridimine-5-carboxylic acid, see: Law et al. (2004). This erbium compound is isostructural with the europium, terbium and ytterbium analogs; see Sun & Jin (2004) for their detailed description.

Experimental top

2,4-Dihydroxypyrimidine-5-carboxylic acid (0.044 g, 0.25 mmol), erbium trichloride hexahydrate (0.096 g, 0.25 mmol), 1,10-phenanthroline (0.050 g, 0.25 mmol), sodium hydroxide (0.010 g, 0.25 mmol) and water (15 ml) was sealed in a 25-ml, Teflon-lined, stainless-steel Parr bomb. The bomb was heated to 383 K for 120 h. It was then cooled over 48 h to give red crystals in 90% yield. CH&N elemental analysis. Found/Calc. for C₃₄H₂₅ErN₈O₁₀: C 46.01; H 2.81, N 13.49% (46.78, 2.89, 12.84%).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: Atomic coordinates taken from published analogs (Sun & Jin, 2004); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top

	Fig. 1. Thermal ellipsoid plot of Er(C₁₂H₈N₂)₂(C₅H₃N₂O₄)(C₅H₂N₂O₄)^.2H₂O drawn at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radii.
	Fig. 2. Square antiprismatic coordination geometry of Er.

(6-Oxido-2-oxo-1,2-dihydropyrimidine-5-carboxylato- κ²O⁵,O⁶)(4-oxido-2-oxo-1,2-dihydropyrimidin-3-ium-5- carboxylato-κ²O⁴,O⁵)bis(1,10-phenanthroline- κ²N,N')erbium(III) dihydrate top

Crystal data top

[Er(C₅H₂N₂O₄)(C₅H₃N₂O₄)(C₁₂H₈N₂)₂]·2H₂O	F(000) = 1732
M_r = 872.88	D_x = 1.804 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 8216 reflections
a = 17.1602 (7) Å	θ = 2.3–28.5°
b = 14.4170 (6) Å	µ = 2.69 mm⁻¹
c = 13.2433 (5) Å	T = 295 K
β = 101.159 (1)°	Prism, red
V = 3214.4 (2) Å³	0.18 × 0.10 × 0.08 mm
Z = 4

Data collection top

Bruker APEXII diffractometer	3680 independent reflections
Radiation source: fine-focus sealed tube	3495 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ϕ and ω scans	θ_max = 27.5°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −22→22
T_min = 0.645, T_max = 0.814	k = −18→18
13567 measured reflections	l = −17→17

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.061	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0387P)² + 2.1981P] where P = (F_o² + 2F_c²)/3
3680 reflections	(Δ/σ)_max = 0.001
240 parameters	Δρ_max = 1.13 e Å⁻³
0 restraints	Δρ_min = −0.38 e Å⁻³

Crystal data top

[Er(C₅H₂N₂O₄)(C₅H₃N₂O₄)(C₁₂H₈N₂)₂]·2H₂O	V = 3214.4 (2) Å³
M_r = 872.88	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 17.1602 (7) Å	µ = 2.69 mm⁻¹
b = 14.4170 (6) Å	T = 295 K
c = 13.2433 (5) Å	0.18 × 0.10 × 0.08 mm
β = 101.159 (1)°

Data collection top

Bruker APEXII diffractometer	3680 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3495 reflections with I > 2σ(I)
T_min = 0.645, T_max = 0.814	R_int = 0.024
13567 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	0 restraints
wR(F²) = 0.061	H-atom parameters constrained
S = 1.05	Δρ_max = 1.13 e Å⁻³
3680 reflections	Δρ_min = −0.38 e Å⁻³
240 parameters

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Er1	0.5000	0.612675 (9)	0.7500	0.02099 (6)
O1	0.26939 (16)	0.37986 (14)	0.36337 (19)	0.0436 (6)
O2	0.40471 (11)	0.56690 (12)	0.61245 (13)	0.0293 (4)
O3	0.43054 (11)	0.50209 (13)	0.81183 (13)	0.0312 (4)
O4	0.34769 (14)	0.39182 (12)	0.84072 (15)	0.0341 (5)
O1W	0.1905 (2)	0.3113 (2)	0.1608 (2)	0.0912 (11)
H1W1	0.2254	0.3253	0.2146	0.137*
H1W2	0.2024	0.2603	0.1354	0.137*
N1	0.28276 (16)	0.33178 (16)	0.53134 (18)	0.0367 (5)
H1N	0.2588	0.2802	0.5137	0.055*	0.50
N2	0.33356 (13)	0.47408 (15)	0.49382 (16)	0.0276 (5)
H2N	0.3385	0.5157	0.4489	0.041*
N3	0.53478 (13)	0.69505 (15)	0.59349 (17)	0.0278 (5)
N4	0.59394 (13)	0.74961 (15)	0.78945 (17)	0.0289 (5)
C1	0.29379 (18)	0.39350 (17)	0.4575 (2)	0.0295 (6)
C2	0.36564 (14)	0.49369 (17)	0.59430 (18)	0.0229 (5)
C3	0.35025 (15)	0.42826 (17)	0.66835 (18)	0.0248 (5)
C4	0.30868 (18)	0.3506 (2)	0.6303 (2)	0.0342 (6)
H4	0.2977	0.3074	0.6777	0.041*
C5	0.37729 (15)	0.44133 (17)	0.78069 (18)	0.0247 (5)
C6	0.50987 (17)	0.6671 (2)	0.4970 (2)	0.0346 (6)
H6	0.4906	0.6070	0.4856	0.042*
C7	0.5112 (2)	0.7236 (3)	0.4122 (2)	0.0486 (8)
H7	0.4946	0.7008	0.3459	0.058*
C8	0.5368 (2)	0.8118 (3)	0.4271 (3)	0.0556 (9)
H8	0.5352	0.8511	0.3710	0.067*
C9	0.5659 (2)	0.8442 (2)	0.5267 (3)	0.0438 (7)
C10	0.56432 (16)	0.78248 (18)	0.6084 (2)	0.0307 (6)
C11	0.5963 (2)	0.9365 (3)	0.5497 (3)	0.0598 (10)
H11	0.5950	0.9787	0.4963	0.072*
C12	0.6260 (2)	0.9627 (2)	0.6459 (3)	0.0586 (10)
H12	0.6457	1.0226	0.6582	0.070*
C13	0.6285 (2)	0.9006 (2)	0.7304 (3)	0.0414 (7)
C14	0.6628 (2)	0.9230 (2)	0.8322 (3)	0.0501 (9)
H14	0.6846	0.9816	0.8475	0.060*
C15	0.6646 (2)	0.8603 (2)	0.9083 (3)	0.0464 (8)
H15	0.6891	0.8743	0.9755	0.056*
C16	0.62887 (17)	0.7737 (2)	0.8840 (2)	0.0365 (6)
H16	0.6297	0.7310	0.9369	0.044*
C17	0.59569 (16)	0.81116 (18)	0.7125 (2)	0.0289 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Er1	0.02696 (10)	0.01677 (9)	0.01709 (9)	0.000	−0.00108 (6)	0.000
O1	0.0548 (14)	0.0334 (12)	0.0366 (12)	−0.0041 (9)	−0.0064 (11)	0.0014 (8)
O2	0.0391 (10)	0.0236 (9)	0.0213 (9)	−0.0088 (8)	−0.0037 (7)	0.0029 (7)
O3	0.0431 (11)	0.0295 (10)	0.0185 (8)	−0.0109 (8)	0.0001 (8)	−0.0010 (7)
O4	0.0482 (13)	0.0337 (11)	0.0205 (10)	−0.0117 (8)	0.0067 (9)	0.0007 (7)
O1W	0.138 (3)	0.0561 (18)	0.0636 (19)	0.0005 (19)	−0.020 (2)	0.0078 (15)
N1	0.0543 (15)	0.0264 (11)	0.0258 (11)	−0.0119 (11)	−0.0012 (10)	−0.0033 (9)
N2	0.0369 (12)	0.0260 (11)	0.0170 (10)	−0.0052 (9)	−0.0019 (8)	0.0019 (8)
N3	0.0300 (11)	0.0262 (11)	0.0268 (11)	0.0003 (9)	0.0044 (9)	0.0020 (9)
N4	0.0279 (11)	0.0259 (11)	0.0318 (12)	−0.0052 (9)	0.0032 (9)	−0.0043 (9)
C1	0.0366 (15)	0.0267 (13)	0.0216 (13)	0.0007 (10)	−0.0037 (11)	−0.0030 (9)
C2	0.0263 (12)	0.0213 (11)	0.0193 (11)	0.0005 (9)	−0.0001 (9)	0.0004 (9)
C3	0.0339 (13)	0.0218 (12)	0.0179 (11)	−0.0048 (10)	0.0030 (10)	−0.0021 (9)
C4	0.0488 (17)	0.0265 (14)	0.0258 (13)	−0.0117 (12)	0.0038 (12)	0.0025 (11)
C5	0.0325 (13)	0.0224 (12)	0.0185 (11)	−0.0001 (10)	0.0033 (9)	0.0000 (9)
C6	0.0353 (14)	0.0391 (15)	0.0288 (14)	−0.0033 (12)	0.0046 (11)	−0.0005 (12)
C7	0.0508 (19)	0.069 (2)	0.0261 (15)	−0.0105 (17)	0.0074 (13)	0.0035 (15)
C8	0.064 (2)	0.065 (2)	0.0360 (18)	−0.0098 (19)	0.0076 (16)	0.0225 (16)
C9	0.0465 (18)	0.0383 (17)	0.0466 (18)	−0.0032 (14)	0.0093 (14)	0.0143 (14)
C10	0.0317 (13)	0.0262 (13)	0.0349 (14)	−0.0009 (11)	0.0085 (11)	0.0053 (11)
C11	0.073 (3)	0.040 (2)	0.066 (3)	−0.0157 (18)	0.014 (2)	0.0201 (18)
C12	0.066 (2)	0.0325 (18)	0.079 (3)	−0.0160 (16)	0.017 (2)	0.0063 (17)
C13	0.0412 (17)	0.0255 (14)	0.060 (2)	−0.0080 (12)	0.0156 (15)	−0.0060 (13)
C14	0.0486 (19)	0.0355 (17)	0.068 (2)	−0.0169 (15)	0.0155 (17)	−0.0174 (17)
C15	0.0415 (17)	0.0477 (18)	0.049 (2)	−0.0117 (15)	0.0063 (15)	−0.0215 (16)
C16	0.0352 (15)	0.0401 (16)	0.0330 (15)	−0.0091 (12)	0.0036 (12)	−0.0077 (12)
C17	0.0269 (13)	0.0220 (12)	0.0383 (15)	−0.0022 (10)	0.0075 (11)	−0.0009 (10)

Geometric parameters (Å, º) top

Er1—O2	2.297 (2)	C2—C3	1.422 (3)
Er1—O2ⁱ	2.297 (2)	C3—C4	1.371 (4)
Er1—O3	2.238 (2)	C3—C5	1.482 (3)
Er1—O3ⁱ	2.238 (2)	C4—H4	0.9300
Er1—N3	2.558 (2)	C6—C7	1.391 (4)
Er1—N3ⁱ	2.558 (2)	C6—H6	0.9300
Er1—N4	2.538 (2)	C7—C8	1.346 (5)
Er1—N4ⁱ	2.538 (2)	C7—H7	0.9300
O1—C1	1.252 (4)	C8—C9	1.398 (5)
O2—C2	1.248 (3)	C8—H8	0.9300
O3—C5	1.275 (3)	C9—C10	1.405 (4)
O4—C5	1.247 (3)	C9—C11	1.440 (5)
O1W—H1W1	0.85	C10—C17	1.441 (4)
O1W—H1W2	0.85	C11—C12	1.332 (6)
N1—C4	1.327 (3)	C11—H11	0.9300
N1—C1	1.362 (4)	C12—C13	1.428 (5)
N1—H1N	0.8600	C12—H12	0.9300
N2—C2	1.368 (3)	C13—C14	1.400 (5)
N2—C1	1.385 (3)	C13—C17	1.409 (4)
N2—H2N	0.8600	C14—C15	1.349 (6)
N3—C6	1.329 (3)	C14—H14	0.9300
N3—C10	1.359 (3)	C15—C16	1.401 (4)
N4—C16	1.326 (4)	C15—H15	0.9300
N4—C17	1.356 (3)	C16—H16	0.9300

O2—Er1—O2ⁱ	146.6 (1)	N1—C4—H4	117.2
O2—Er1—O3	74.8 (1)	C3—C4—H4	117.2
O2—Er1—O3ⁱ	81.6 (1)	O4—C5—O3	122.8 (2)
O2—Er1—N3	74.5 (1)	O4—C5—C3	118.7 (2)
O2—Er1—N3ⁱ	122.3 (1)	O3—C5—C3	118.5 (2)
O2—Er1—N4	135.5 (1)	N3—C6—C7	123.1 (3)
O2—Er1—N4ⁱ	74.6 (1)	N3—C6—H6	118.5
O3—Er1—O3ⁱ	89.2 (1)	C7—C6—H6	118.5
O3—Er1—N3	148.4 (1)	C8—C7—C6	119.4 (3)
O3—Er1—N3ⁱ	79.0 (1)	C8—C7—H7	120.3
O3—Er1—N4	147.2 (1)	C6—C7—H7	120.3
O3—Er1—N4ⁱ	105.5 (1)	C7—C8—C9	120.0 (3)
N3—Er1—N3ⁱ	124.7 (1)	C7—C8—H8	120.0
N3—Er1—N4	64.4 (1)	C9—C8—H8	120.0
N3—Er1—N4ⁱ	73.2 (1)	C8—C9—C10	117.3 (3)
N4—Er1—N4ⁱ	77.9 (1)	C8—C9—C11	123.9 (3)
C2—O2—Er1	131.99 (15)	C10—C9—C11	118.9 (3)
C5—O3—Er1	140.34 (16)	N3—C10—C9	122.6 (3)
H1W1—O1W—H1W2	110.3	N3—C10—C17	117.7 (2)
C4—N1—C1	120.6 (2)	C9—C10—C17	119.7 (3)
C4—N1—H1N	119.7	C12—C11—C9	121.4 (3)
C1—N1—H1N	119.7	C12—C11—H11	119.3
C2—N2—C1	126.1 (2)	C9—C11—H11	119.3
C2—N2—H2N	116.9	C11—C12—C13	121.3 (3)
C1—N2—H2N	116.9	C11—C12—H12	119.3
C6—N3—C10	117.5 (2)	C13—C12—H12	119.3
C6—N3—Er1	123.81 (18)	C14—C13—C17	116.9 (3)
C10—N3—Er1	116.89 (17)	C14—C13—C12	123.6 (3)
C16—N4—C17	117.8 (2)	C17—C13—C12	119.5 (3)
C16—N4—Er1	123.46 (19)	C15—C14—C13	120.6 (3)
C17—N4—Er1	117.38 (16)	C15—C14—H14	119.7
O1—C1—N1	123.1 (2)	C13—C14—H14	119.7
O1—C1—N2	121.6 (2)	C14—C15—C16	118.7 (3)
N1—C1—N2	115.2 (2)	C14—C15—H15	120.7
O2—C2—N2	117.5 (2)	C16—C15—H15	120.7
O2—C2—C3	126.3 (2)	N4—C16—C15	123.2 (3)
N2—C2—C3	116.1 (2)	N4—C16—H16	118.4
C4—C3—C2	116.2 (2)	C15—C16—H16	118.4
C4—C3—C5	120.8 (2)	N4—C17—C13	122.6 (3)
C2—C3—C5	123.0 (2)	N4—C17—C10	118.2 (2)
N1—C4—C3	125.5 (3)	C13—C17—C10	119.2 (3)

O3—Er1—O2—C2	−23.0 (2)	O2—C2—C3—C4	−177.3 (3)
O3ⁱ—Er1—O2—C2	68.4 (2)	N2—C2—C3—C4	3.4 (4)
O2ⁱ—Er1—O2—C2	23.4 (2)	O2—C2—C3—C5	2.4 (4)
N4—Er1—O2—C2	172.0 (2)	N2—C2—C3—C5	−176.9 (2)
N4ⁱ—Er1—O2—C2	−134.2 (2)	C1—N1—C4—C3	−2.7 (5)
N3ⁱ—Er1—O2—C2	−89.1 (2)	C2—C3—C4—N1	0.6 (5)
N3—Er1—O2—C2	149.3 (2)	C5—C3—C4—N1	−179.1 (3)
O3ⁱ—Er1—O3—C5	−72.0 (3)	Er1—O3—C5—O4	−175.83 (19)
O2—Er1—O3—C5	9.5 (3)	Er1—O3—C5—C3	5.0 (4)
O2ⁱ—Er1—O3—C5	−146.7 (3)	C4—C3—C5—O4	−15.3 (4)
N4—Er1—O3—C5	169.9 (2)	C2—C3—C5—O4	165.0 (3)
N4ⁱ—Er1—O3—C5	78.3 (3)	C4—C3—C5—O3	163.9 (3)
N3ⁱ—Er1—O3—C5	137.6 (3)	C2—C3—C5—O3	−15.7 (4)
N3—Er1—O3—C5	−4.7 (3)	C10—N3—C6—C7	−1.4 (4)
O3—Er1—N3—C6	−6.7 (3)	Er1—N3—C6—C7	162.9 (2)
O3ⁱ—Er1—N3—C6	63.3 (2)	N3—C6—C7—C8	−1.8 (5)
O2—Er1—N3—C6	−20.9 (2)	C6—C7—C8—C9	3.6 (6)
O2ⁱ—Er1—N3—C6	127.3 (2)	C7—C8—C9—C10	−2.2 (5)
N4—Er1—N3—C6	176.5 (2)	C7—C8—C9—C11	178.5 (4)
N4ⁱ—Er1—N3—C6	−99.1 (2)	C6—N3—C10—C9	2.9 (4)
N3ⁱ—Er1—N3—C6	−139.7 (2)	Er1—N3—C10—C9	−162.5 (2)
O3—Er1—N3—C10	157.69 (17)	C6—N3—C10—C17	−176.4 (2)
O3ⁱ—Er1—N3—C10	−132.33 (19)	Er1—N3—C10—C17	18.2 (3)
O2—Er1—N3—C10	143.5 (2)	C8—C9—C10—N3	−1.1 (5)
O2ⁱ—Er1—N3—C10	−68.3 (2)	C11—C9—C10—N3	178.3 (3)
N4—Er1—N3—C10	−19.07 (17)	C8—C9—C10—C17	178.2 (3)
N4ⁱ—Er1—N3—C10	65.31 (19)	C11—C9—C10—C17	−2.4 (5)
N3ⁱ—Er1—N3—C10	24.68 (17)	C8—C9—C11—C12	−177.4 (4)
O3—Er1—N4—C16	8.6 (3)	C10—C9—C11—C12	3.2 (6)
O3ⁱ—Er1—N4—C16	−105.1 (2)	C9—C11—C12—C13	−0.6 (7)
O2—Er1—N4—C16	161.2 (2)	C11—C12—C13—C14	176.5 (4)
O2ⁱ—Er1—N4—C16	−36.1 (2)	C11—C12—C13—C17	−2.7 (6)
N4ⁱ—Er1—N4—C16	108.5 (2)	C17—C13—C14—C15	0.7 (5)
N3ⁱ—Er1—N4—C16	41.9 (2)	C12—C13—C14—C15	−178.6 (4)
N3—Er1—N4—C16	−174.5 (2)	C13—C14—C15—C16	−2.3 (5)
O3—Er1—N4—C17	−157.77 (17)	C17—N4—C16—C15	2.3 (4)
O3ⁱ—Er1—N4—C17	88.48 (19)	Er1—N4—C16—C15	−164.0 (2)
O2—Er1—N4—C17	−5.2 (2)	C14—C15—C16—N4	0.8 (5)
O2ⁱ—Er1—N4—C17	157.4 (2)	C16—N4—C17—C13	−4.1 (4)
N4ⁱ—Er1—N4—C17	−57.88 (17)	Er1—N4—C17—C13	163.1 (2)
N3ⁱ—Er1—N4—C17	−124.5 (2)	C16—N4—C17—C10	174.5 (2)
N3—Er1—N4—C17	19.09 (18)	Er1—N4—C17—C10	−18.3 (3)
C4—N1—C1—O1	−178.8 (3)	C14—C13—C17—N4	2.6 (4)
C4—N1—C1—N2	0.5 (4)	C12—C13—C17—N4	−178.1 (3)
C2—N2—C1—O1	−176.8 (3)	C14—C13—C17—C10	−175.9 (3)
C2—N2—C1—N1	3.9 (4)	C12—C13—C17—C10	3.4 (4)
Er1—O2—C2—N2	−158.37 (17)	N3—C10—C17—N4	−0.1 (4)
Er1—O2—C2—C3	22.3 (4)	C9—C10—C17—N4	−179.4 (3)
C1—N2—C2—O2	174.7 (3)	N3—C10—C17—C13	178.5 (3)
C1—N2—C2—C3	−5.9 (4)	C9—C10—C17—C13	−0.8 (4)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1n···N1ⁱⁱ	0.86	1.82	2.675 (5)	174
N2—H2n···O4ⁱⁱⁱ	0.86	1.99	2.846 (3)	178
O1w—H1w1···O1	0.85	2.12	2.933 (4)	157
O1w—H1w2···O4ⁱⁱ	0.85	2.40	3.000 (4)	128

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

Experimental details

Crystal data
Chemical formula	[Er(C₅H₂N₂O₄)(C₅H₃N₂O₄)(C₁₂H₈N₂)₂]·2H₂O
M_r	872.88
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	295
a, b, c (Å)	17.1602 (7), 14.4170 (6), 13.2433 (5)
β (°)	101.159 (1)
V (Å³)	3214.4 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.69
Crystal size (mm)	0.18 × 0.10 × 0.08

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.645, 0.814
No. of measured, independent and observed [I > 2σ(I)] reflections	13567, 3680, 3495
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.061, 1.05
No. of reflections	3680
No. of parameters	240
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.13, −0.38

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), Atomic coordinates taken from published analogs (Sun & Jin, 2004), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).

Selected geometric parameters (Å, º) top

Er1—O2	2.297 (2)	Er1—N3	2.558 (2)
Er1—O3	2.238 (2)	Er1—N4	2.538 (2)

O2—Er1—O2ⁱ	146.6 (1)	O3—Er1—N3	148.4 (1)
O2—Er1—O3	74.8 (1)	O3—Er1—N3ⁱ	79.0 (1)
O2—Er1—O3ⁱ	81.6 (1)	O3—Er1—N4	147.2 (1)
O2—Er1—N3	74.5 (1)	O3—Er1—N4ⁱ	105.5 (1)
O2—Er1—N3ⁱ	122.3 (1)	N3—Er1—N3ⁱ	124.7 (1)
O2—Er1—N4	135.5 (1)	N3—Er1—N4	64.4 (1)
O2—Er1—N4ⁱ	74.6 (1)	N3—Er1—N4ⁱ	73.2 (1)
O3—Er1—O3ⁱ	89.2 (1)	N4—Er1—N4ⁱ	77.9 (1)

Symmetry code: (i) −x+1, y, −z+3/2.

Acknowledgements

The authors thank the Scientifc Research Foundation of Guangxi Normal University, China, the Science Foundation of Guangxi Province, China (Grant No. 0542021) and the University of Malaya for supporting this study.

References

Barbour, L. J. (2001). J. Supramol. Chem., 1, 189–191. CrossRef CAS Google Scholar
Bruker (2006). APEX2 (Version 1.22A) and SAINT (Version 7.12A). Bruker AXS Inc., Madison, Winconsin, USA. Google Scholar
Law, G.-L., Szeto, L. & Wong, W.-T. (2004). Acta Cryst. E60, o1072–o1074. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sun, C.-Y. & Jin, L. P. (2004). Polyhedron, 23, 2085–2093. Web of Science CSD CrossRef CAS Google Scholar
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