Tetra­aqua­(nitrato-κ2O,O′)bis­(pyridinium-4-carboxyl­ate-κO)europium(III) dinitrate

Zhong, Z.-G.; Song, J.-F.; Li, J.; Meng, Z.-H.

doi:10.1107/S1600536811014772

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 5| May 2011| Page m637

doi:10.1107/S1600536811014772

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Tetraaqua(nitrato-κ²O,O′)bis(pyridinium-4-carboxylate-κO)europium(III) dinitrate

Zhi-Guo Zhong,^a ^* Jin-Fan Song,^b Jing Li ^c and Zhao-Hui Meng ^d

^aCenter of Analysis and Testing, Nanyang Normal University, Nanyang 473061, People's Republic of China, ^bSchool of Physics and Electronic Engineering, Nanyang Normal University, Nanyang 473061, People's Republic of China, ^cSchool of Mathematics and Statistics, Nanyang Normal University, Nanyang 473061, People's Republic of China, and ^dCollege of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473061, People's Republic of China
^*Correspondence e-mail: zhongzhiguo1978@126.com

(Received 7 April 2011; accepted 20 April 2011; online 29 April 2011)

The asymmetric unit of the title compound, [Eu(NO₃)(C₆H₅NO₂)₂(H₂O)₄](NO₃)₂, consists of one-half of the C₂ symmetric coordination cation and one nitrate anion. The eight-coordinated Eu^III atom is in a distorted dodecahedral coordination environment. The coordination cations and nitrate anions are connected via O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional network.

Related literature

For photophysical properties of lanthanide(III) coordination compounds, see, for example: Jüstel et al. (1998 ); Xu et al. (2010 ). For potential applications of lanthanide(III) coordination compounds as light-conversion molecular devices, see, for example: Lehn (1990 ).

Experimental

Crystal data

[Eu(NO₃)(C₆H₅NO₂)₂(H₂O)₄](NO₃)₂
M_r = 656.27
Monoclinic, C 2/c
a = 14.612 (4) Å
b = 12.498 (4) Å
c = 13.342 (4) Å
β = 118.728 (4)°
V = 2136.6 (11) Å³
Z = 4
Mo Kα radiation
μ = 3.03 mm⁻¹
T = 293 K
0.35 × 0.32 × 0.28 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan SADABS (Bruker, 1997 ) T_min = 0.417, T_max = 0.484
5224 measured reflections
1881 independent reflections
1847 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.015
wR(F²) = 0.038
S = 1.02
1881 reflections
180 parameters
8 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.58 e Å⁻³
Δρ_min = −0.62 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WB⋯O7ⁱ	0.81 (2)	1.99 (2)	2.790 (2)	175 (3)
O1W—H1WA⋯O1ⁱⁱ	0.83 (2)	1.87 (2)	2.653 (2)	155 (2)
O2W—H2WB⋯O1ⁱⁱⁱ	0.83 (2)	1.84 (2)	2.661 (2)	173 (3)
O2W—H2WA⋯O5	0.82 (2)	2.23 (2)	2.958 (3)	148 (3)
N1—H6⋯O7^iv	0.94 (3)	1.88 (3)	2.814 (3)	179 (3)
Symmetry codes: (i) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (ii) $[-x, y, -z+{\script{1\over 2}}]$ ; (iii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); 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); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811014772/gk2366sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811014772/gk2366Isup2.hkl

checkCIF report

Comment top

The lanthanide (III) coordination compounds have attracted considerable attention due to their interesting photophysical properties and their potential application as light-conversion molecular devices. Herein, we report a new rare-earth metal–organic compound [Eu(C₆H₅NO₂)₂(H₂O)₄(NO₃)](NO₃)₂. The structural unit of the title compound consists of one coordination cation which has a crystallographic twofold axis symmetry, [Eu(C₆H₅NO₂)₂(H₂O)₄(NO₃)]²⁺, and two nitrate anions (Fig. 1). In the coordination cation the Eu(III) center is coordinated by eight O atoms: two from C₆H₅NO₂ ligands, two from NO₃^-anion and four from water molecules. The coordination geometry around the Eu(III) center can be described as dodecahedral with O—Eu—O bond angles ranging from 51.07 (10) to 152.96 (9)° and the Eu—O bond lengths ranging from 2.3614 (16) to 2.5000 (19) Å. The electrostatic interactions and hydrogen bonds result in the formation of three-dimensional network (Fig. 2). Obviously, electrostatic interactions and hydrogen bonds play a crucial role in the chemical stability of the title compound.

Related literature top

For photophysical properties of lanthanide(III) coordination compounds, see, for example: Jüstel et al. (1998); Xu et al. (2010). For potential applications of lanthanide(III) coordination compounds as light-conversion molecular devices, see, for example: Lehn (1990).

Experimental top

All chemicals were of reagent grade quality obtained from commercial sources and used without further purification. 0.24 g of isonicotinic acid (1 mmol) and 0.45 g Eu(NO₃)₃.6H₂O (1 mmol) were dissolved in 30 ml of distilled water. Then pH of the mixture was carefully adjusted to 5.0 with 1M HCl solution. After stirring for half an hour, the solution was filtered and left for slowly evaporation at room temperature to obtain colorless crystals suitable for X-ray structure determination.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. View of the title compound with displacement ellipsoids drawn at the 30% probability level . Symmetry code for the atoms with the label A: -x, y, -z + 1/2.
	Fig. 2. Crystal packing viewed along the c axis. Hydrogen bonds are shown with dashed lines.

Tetraaqua(nitrato-κ²O,O')bis(pyridinium-4-carboxylate- κO)europium(III) dinitrate top

Crystal data top

[Eu(NO₃)(C₆H₅NO₂)₂(H₂O)₄](NO₃)₂	F(000) = 1296
M_r = 656.27	D_x = 2.040 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5781 reflections
a = 14.612 (4) Å	θ = 2.3–28.3°
b = 12.498 (4) Å	µ = 3.03 mm⁻¹
c = 13.342 (4) Å	T = 293 K
β = 118.728 (4)°	Block, colourless
V = 2136.6 (11) Å³	0.35 × 0.32 × 0.28 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	1881 independent reflections
Radiation source: fine-focus sealed tube	1847 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.3°
Absorption correction: multi-scan SADABS (Bruker, 1997)	h = −13→17
T_min = 0.417, T_max = 0.484	k = −14→12
5224 measured reflections	l = −15→15

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)] = 0.015	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.038	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ²(F_o²) + (0.0211P)² + 2.5852P] where P = (F_o² + 2F_c²)/3
1881 reflections	(Δ/σ)_max = 0.001
180 parameters	Δρ_max = 0.58 e Å⁻³
8 restraints	Δρ_min = −0.62 e Å⁻³

Crystal data top

[Eu(NO₃)(C₆H₅NO₂)₂(H₂O)₄](NO₃)₂	V = 2136.6 (11) Å³
M_r = 656.27	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 14.612 (4) Å	µ = 3.03 mm⁻¹
b = 12.498 (4) Å	T = 293 K
c = 13.342 (4) Å	0.35 × 0.32 × 0.28 mm
β = 118.728 (4)°

Data collection top

Bruker APEXII CCD diffractometer	1881 independent reflections
Absorption correction: multi-scan SADABS (Bruker, 1997)	1847 reflections with I > 2σ(I)
T_min = 0.417, T_max = 0.484	R_int = 0.017
5224 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.015	8 restraints
wR(F²) = 0.038	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	Δρ_max = 0.58 e Å⁻³
1881 reflections	Δρ_min = −0.62 e Å⁻³
180 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.

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

	x	y	z	U_iso*/U_eq
Eu1	0.0000	0.184699 (10)	0.2500	0.02398 (6)
O1	0.27428 (13)	0.30594 (12)	0.37370 (16)	0.0421 (4)
O1W	−0.17399 (12)	0.12138 (14)	0.15960 (17)	0.0453 (4)
H1WB	−0.199 (2)	0.0622 (15)	0.144 (2)	0.044 (8)*
H1WA	−0.2202 (13)	0.1684 (17)	0.134 (3)	0.063 (10)*
O2	0.10558 (12)	0.33068 (12)	0.25718 (14)	0.0350 (4)
O2W	−0.04309 (13)	0.22924 (14)	0.05884 (14)	0.0390 (4)
H2WB	−0.0982 (17)	0.213 (2)	0.002 (2)	0.051 (8)*
H2WA	−0.021 (2)	0.2840 (19)	0.045 (3)	0.061 (10)*
O3	0.00037 (14)	0.00420 (15)	0.33097 (17)	0.0495 (4)
O4	0.0000	−0.1458 (2)	0.2500	0.1018 (15)
O5	0.08162 (14)	0.35758 (14)	−0.01819 (16)	0.0462 (4)
O6	0.11039 (14)	0.52783 (13)	−0.00657 (16)	0.0471 (4)
O7	0.23063 (12)	0.42067 (12)	0.10876 (14)	0.0386 (4)
N1	0.23834 (19)	0.69898 (16)	0.3531 (2)	0.0390 (5)
N2	0.0000	−0.0487 (2)	0.2500	0.0506 (9)
N3	0.13887 (14)	0.43631 (14)	0.02637 (16)	0.0312 (4)
C1	0.3165 (2)	0.63532 (19)	0.4224 (2)	0.0403 (5)
H1	0.3784	0.6647	0.4788	0.048*
C2	0.30538 (18)	0.52613 (18)	0.4104 (2)	0.0353 (5)
H2	0.3604	0.4813	0.4567	0.042*
C3	0.21208 (16)	0.48366 (16)	0.32907 (17)	0.0262 (4)
C4	0.13218 (17)	0.55193 (17)	0.25749 (19)	0.0317 (5)
H4	0.0691	0.5246	0.2012	0.038*
C5	0.1479 (2)	0.65997 (19)	0.2713 (2)	0.0387 (5)
H5	0.0954	0.7066	0.2235	0.046*
C6	0.19639 (16)	0.36402 (16)	0.31971 (17)	0.0270 (4)
H6	0.248 (2)	0.773 (3)	0.367 (2)	0.050 (8)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Eu1	0.01991 (9)	0.01759 (9)	0.02573 (9)	0.000	0.00400 (6)	0.000
O1	0.0282 (8)	0.0270 (8)	0.0463 (10)	0.0018 (6)	−0.0019 (8)	0.0010 (7)
O1W	0.0250 (8)	0.0221 (9)	0.0734 (13)	−0.0035 (7)	0.0112 (8)	−0.0035 (8)
O2	0.0258 (8)	0.0258 (8)	0.0379 (9)	−0.0057 (6)	0.0028 (7)	0.0032 (6)
O2W	0.0332 (9)	0.0382 (10)	0.0296 (8)	−0.0127 (8)	0.0023 (7)	0.0047 (7)
O3	0.0463 (10)	0.0388 (10)	0.0516 (11)	−0.0004 (8)	0.0140 (9)	0.0148 (8)
O4	0.088 (3)	0.0177 (14)	0.202 (5)	0.000	0.071 (3)	0.000
O5	0.0419 (10)	0.0339 (9)	0.0486 (10)	−0.0067 (8)	0.0104 (8)	−0.0042 (8)
O6	0.0487 (10)	0.0281 (9)	0.0581 (11)	0.0106 (8)	0.0207 (9)	0.0114 (8)
O7	0.0331 (8)	0.0291 (8)	0.0428 (9)	0.0014 (6)	0.0098 (7)	0.0034 (7)
N1	0.0544 (13)	0.0233 (10)	0.0466 (12)	−0.0076 (9)	0.0302 (11)	−0.0047 (8)
N2	0.0305 (15)	0.0215 (14)	0.083 (3)	0.000	0.0135 (16)	0.000
N3	0.0333 (10)	0.0281 (10)	0.0337 (10)	0.0021 (8)	0.0172 (8)	0.0016 (8)
C1	0.0452 (14)	0.0326 (13)	0.0373 (13)	−0.0140 (11)	0.0151 (11)	−0.0061 (10)
C2	0.0327 (11)	0.0286 (12)	0.0336 (12)	−0.0056 (9)	0.0070 (10)	0.0001 (9)
C3	0.0277 (10)	0.0254 (10)	0.0253 (10)	−0.0023 (8)	0.0127 (9)	−0.0003 (8)
C4	0.0275 (10)	0.0288 (11)	0.0359 (12)	0.0009 (9)	0.0127 (9)	0.0017 (9)
C5	0.0438 (14)	0.0271 (11)	0.0479 (14)	0.0064 (10)	0.0242 (12)	0.0051 (10)
C6	0.0255 (10)	0.0237 (11)	0.0239 (10)	−0.0034 (8)	0.0056 (8)	−0.0015 (8)

Geometric parameters (Å, º) top

Eu1—O2	2.3614 (16)	O5—N3	1.242 (3)
Eu1—O2ⁱ	2.3614 (16)	O6—N3	1.224 (2)
Eu1—O1W	2.3657 (17)	O7—N3	1.276 (2)
Eu1—O1Wⁱ	2.3657 (17)	N1—C1	1.333 (4)
Eu1—O2Wⁱ	2.3806 (18)	N1—C5	1.337 (4)
Eu1—O2W	2.3806 (18)	N1—H6	0.94 (3)
Eu1—O3ⁱ	2.5000 (19)	N2—O3ⁱ	1.264 (2)
Eu1—O3	2.5000 (19)	C1—C2	1.375 (3)
Eu1—N2	2.917 (3)	C1—H1	0.9300
O1—C6	1.246 (3)	C2—C3	1.377 (3)
O1W—H1WB	0.805 (17)	C2—H2	0.9300
O1W—H1WA	0.834 (16)	C3—C4	1.390 (3)
O2—C6	1.251 (3)	C3—C6	1.509 (3)
O2W—H2WB	0.826 (17)	C4—C5	1.367 (3)
O2W—H2WA	0.818 (18)	C4—H4	0.9300
O3—N2	1.264 (2)	C5—H5	0.9300
O4—N2	1.214 (4)

O2—Eu1—O2ⁱ	78.82 (8)	Eu1—O1W—H1WA	115.7 (15)
O2—Eu1—O1W	143.15 (6)	H1WB—O1W—H1WA	111 (2)
O2ⁱ—Eu1—O1W	73.54 (6)	C6—O2—Eu1	138.33 (14)
O2—Eu1—O1Wⁱ	73.54 (6)	Eu1—O2W—H2WB	125 (2)
O2ⁱ—Eu1—O1Wⁱ	143.15 (6)	Eu1—O2W—H2WA	121 (2)
O1W—Eu1—O1Wⁱ	140.91 (8)	H2WB—O2W—H2WA	109 (3)
O2—Eu1—O2Wⁱ	86.83 (6)	N2—O3—Eu1	95.99 (15)
O2ⁱ—Eu1—O2Wⁱ	72.18 (6)	C1—N1—C5	122.0 (2)
O1W—Eu1—O2Wⁱ	106.89 (7)	C1—N1—H6	116.8 (18)
O1Wⁱ—Eu1—O2Wⁱ	82.30 (7)	C5—N1—H6	121.2 (18)
O2—Eu1—O2W	72.18 (6)	O4—N2—O3	121.53 (14)
O2ⁱ—Eu1—O2W	86.83 (6)	O4—N2—O3ⁱ	121.53 (14)
O1W—Eu1—O2W	82.30 (7)	O3—N2—O3ⁱ	116.9 (3)
O1Wⁱ—Eu1—O2W	106.89 (7)	O4—N2—Eu1	180.0
O2Wⁱ—Eu1—O2W	152.96 (9)	O3—N2—Eu1	58.47 (14)
O2—Eu1—O3ⁱ	125.48 (7)	O3ⁱ—N2—Eu1	58.47 (14)
O2ⁱ—Eu1—O3ⁱ	144.49 (6)	O6—N3—O5	122.3 (2)
O1W—Eu1—O3ⁱ	72.50 (6)	O6—N3—O7	119.18 (19)
O1Wⁱ—Eu1—O3ⁱ	72.37 (6)	O5—N3—O7	118.56 (18)
O2Wⁱ—Eu1—O3ⁱ	128.20 (6)	N1—C1—C2	119.9 (2)
O2W—Eu1—O3ⁱ	78.67 (7)	N1—C1—H1	120.1
O2—Eu1—O3	144.49 (6)	C2—C1—H1	120.1
O2ⁱ—Eu1—O3	125.48 (7)	C1—C2—C3	119.4 (2)
O1W—Eu1—O3	72.37 (6)	C1—C2—H2	120.3
O1Wⁱ—Eu1—O3	72.50 (6)	C3—C2—H2	120.3
O2Wⁱ—Eu1—O3	78.67 (7)	C2—C3—C4	119.4 (2)
O2W—Eu1—O3	128.20 (6)	C2—C3—C6	120.06 (19)
O3ⁱ—Eu1—O3	51.07 (10)	C4—C3—C6	120.50 (19)
O2—Eu1—N2	140.59 (4)	C5—C4—C3	118.8 (2)
O2ⁱ—Eu1—N2	140.59 (4)	C5—C4—H4	120.6
O1W—Eu1—N2	70.46 (4)	C3—C4—H4	120.6
O1Wⁱ—Eu1—N2	70.46 (4)	N1—C5—C4	120.4 (2)
O2Wⁱ—Eu1—N2	103.52 (4)	N1—C5—H5	119.8
O2W—Eu1—N2	103.52 (4)	C4—C5—H5	119.8
O3ⁱ—Eu1—N2	25.54 (5)	O1—C6—O2	124.92 (19)
O3—Eu1—N2	25.54 (5)	O1—C6—C3	117.98 (18)
Eu1—O1W—H1WB	133 (2)	O2—C6—C3	117.09 (18)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WB···O7ⁱⁱ	0.81 (2)	1.99 (2)	2.790 (2)	175 (3)
O1W—H1WA···O1ⁱ	0.83 (2)	1.87 (2)	2.653 (2)	155 (2)
O2W—H2WB···O1ⁱⁱⁱ	0.83 (2)	1.84 (2)	2.661 (2)	173 (3)
O2W—H2WA···O5	0.82 (2)	2.23 (2)	2.958 (3)	148 (3)
N1—H6···O7^iv	0.94 (3)	1.88 (3)	2.814 (3)	179 (3)

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

Experimental details

Crystal data
Chemical formula	[Eu(NO₃)(C₆H₅NO₂)₂(H₂O)₄](NO₃)₂
M_r	656.27
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	14.612 (4), 12.498 (4), 13.342 (4)
β (°)	118.728 (4)
V (Å³)	2136.6 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.03
Crystal size (mm)	0.35 × 0.32 × 0.28

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan SADABS (Bruker, 1997)
T_min, T_max	0.417, 0.484
No. of measured, independent and observed [I > 2σ(I)] reflections	5224, 1881, 1847
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.015, 0.038, 1.02
No. of reflections	1881
No. of parameters	180
No. of restraints	8
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.58, −0.62

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WB···O7ⁱ	0.805 (17)	1.988 (18)	2.790 (2)	175 (3)
O1W—H1WA···O1ⁱⁱ	0.834 (16)	1.87 (2)	2.653 (2)	155 (2)
O2W—H2WB···O1ⁱⁱⁱ	0.826 (17)	1.839 (18)	2.661 (2)	173 (3)
O2W—H2WA···O5	0.818 (18)	2.23 (2)	2.958 (3)	148 (3)
N1—H6···O7^iv	0.94 (3)	1.88 (3)	2.814 (3)	179 (3)

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

References

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