Poly[[tetra­kis­(μ2-pyrazine N,N′-dioxide-κ2O:O′)erbium(III)] tris­(perchlorate)]

Buchner, J.D.; Quinn-Elmore, B.G.; Beach, K.B.; Knaust, J.M.

doi:10.1107/S1600536810031843

metal-organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 9| September 2010| Pages m1110-m1111

https://doi.org/10.1107/S1600536810031843

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Poly[[tetrakis(μ₂-pyrazine N,N′-dioxide-κ²O:O′)erbium(III)] tris(perchlorate)]

James D. Buchner,^a Benjamin G. Quinn-Elmore,^a Keith B. Beach ^a and Jacqueline M. Knaust ^a ^*

^aAllegheny College, 520 North Main St., Meadville, PA 16335, USA
^*Correspondence e-mail: jknaust@allegheny.edu

(Received 3 August 2010; accepted 9 August 2010; online 18 August 2010)

The title three-dimensional coordination network, {[Er(C₄H₄N₂O₂)₄](ClO₄)₃}_n, is isostructural to that of other lanthanides. The Er⁺³cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-antiprismatic fashion by eight O atoms from bridging pyrazine N,N′-dioxide ligands. There are two unique pyrazine N,N′-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and interact with the coordination network through C—H⋯O hydrogen bonds.

Related literature

For the isostructural La, Ce, Pr, Sm, Eu, Gd, Tb and Y coordination networks, see: Sun et al. (2004 ). For the isostructural Nd, Dy and Ho coordination networks, see: Quinn-Elmore et al. (2010a ,b ); Buchner et al. (2010 ), respectively. Detailed background to this study is described in the first article of this series by Quinn-Elmore et al. (2010a).

Experimental

Crystal data

[Er(C₄H₄N₂O₂)₄](ClO₄)₃
M_r = 913.98
Tetragonal, I 4₁ /a c d
a = 15.1777 (4) Å
c = 22.5094 (12) Å
V = 5185.3 (3) Å³
Z = 8
Mo Kα radiation
μ = 3.66 mm⁻¹
T = 100 K
0.44 × 0.44 × 0.18 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.725, T_max = 1.000
27002 measured reflections
1997 independent reflections
1775 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.092
S = 0.98
1997 reflections
110 parameters
H-atom parameters constrained
Δρ_max = 3.41 e Å⁻³
Δρ_min = −1.62 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O2ⁱ	0.95	2.50	3.266 (3)	138
C2—H2⋯O5	0.95	2.39	3.147 (5)	137
C3—H3⋯O1	0.95	2.60	3.321 (3)	133
C3—H3⋯O3	0.95	2.45	3.219 (3)	138
C4—H4⋯O3ⁱⁱ	0.95	2.35	3.218 (3)	152
Symmetry codes: (i) $[-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[-y+{\script{3\over 4}}, x-{\script{1\over 4}}, -z+{\script{1\over 4}}]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: X-SEED.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810031843/zl2301sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810031843/zl2301Isup2.hkl

checkCIF report

Comment top

The description of the structure of the title compound is part of a series of consecutive papers on three-dimensional coordination networks of the type {[Ln(C₄H₄N₂O₂)₄](ClO₄)₃}_n, with Ln = Nd (Quinn-Elmore et al. 2010a), Dy (Quinn-Elmore et al. 2010b) and Ho (Buchner et al. 2010), Er (this publication), respectively. All four compounds are also isostructural to the previously reported La, Ce, Pr, Sm, Eu, Gd, Tb and Y coordination networks (Sun et al. 2004). The background to this study is given in ther first article of this series by Quinn-Elmore et al. (2010a).

Related literature top

For the isostructural La, Ce, Pr, Sm, Eu, Gd, Tb and Y coordination networks, see: Sun et al. (2004). For the isostructural Nd, Dy and Ho coordination networks, see: Quinn-Elmore et al. (2010a,b); Buchner et al. (2010), respectively. Detailed background to this study is described in the first article of this series by Quinn-Elmore et al. (2010a).

Experimental top

Pyrazine N,N'-dioxide (0.025 g, 0.223 mmol) was dissolved in deionized water (1.5 ml) and methanol (1.5 ml). An aqueous solution of Er(ClO₄)₃ (0.650 ml of a 0.0860 M solution, 0.0558 mmol) was diluted with methanol (0.350 ml) and CH₂Cl₂ (2.5 ml). The pyrazine N,N'-dioxide solution was layered over the Er(ClO₄)₃ solution, and the two solutions were allowed to slowly mix. Yellow block-like crystals formed upon the slow evaporation of the resultant solution.

Structure description top

For the isostructural La, Ce, Pr, Sm, Eu, Gd, Tb and Y coordination networks, see: Sun et al. (2004). For the isostructural Nd, Dy and Ho coordination networks, see: Quinn-Elmore et al. (2010a,b); Buchner et al. (2010), respectively. Detailed background to this study is described in the first article of this series by Quinn-Elmore et al. (2010a).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: X-SEED (Barbour, 2001).

Figures top

Fig. 1. The coordination environment of the Er⁺³ cation in title compound with atom labels and 50% probability displacement ellipsoids. Hydrogen atoms have been omitted for clarity. Symmetry codes: (i) y + 1/4, x - 1/4, -z + 3/4; (ii) -y + 3/4, -x + 3/4, -z + 3/4; (iii) -x + 1, -y + 1/2, z; (iv) -y + 3/4, x - 1/4, -z + 1/4; (v) y + 1/4, -x + 3/4, -z + 1/4; (vi) y + 3/4, x - 3/4, -z + 1/4; (vii) -x + 3/2, -y + 1/2, -z + 1/2; (viii) x, -y + 1, -z + 1/2.

Poly[[tetrakis(µ₂-pyrazine N,N'-dioxide-κ²O:O')erbium(III)] tris(perchlorate)] top

Crystal data top

[Er(C₄H₄N₂O₂)₄](ClO₄)₃	D_x = 2.342 Mg m⁻³
M_r = 913.98	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4₁/acd	Cell parameters from 13828 reflections
Hall symbol: -I 4bd 2c	θ = 2.6–30.6°
a = 15.1777 (4) Å	µ = 3.66 mm⁻¹
c = 22.5094 (12) Å	T = 100 K
V = 5185.3 (3) Å³	Block, yellow
Z = 8	0.44 × 0.44 × 0.18 mm
F(000) = 3576

Data collection top

Bruker SMART APEX CCD diffractometer	1997 independent reflections
Radiation source: fine-focus sealed tube	1775 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ω scans	θ_max = 30.6°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −21→21
T_min = 0.725, T_max = 1.000	k = −21→21
27002 measured reflections	l = −32→32

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.092	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0554P)² + 37.1849P] where P = (F_o² + 2F_c²)/3
1997 reflections	(Δ/σ)_max = 0.001
110 parameters	Δρ_max = 3.41 e Å⁻³
0 restraints	Δρ_min = −1.62 e Å⁻³

Crystal data top

[Er(C₄H₄N₂O₂)₄](ClO₄)₃	Z = 8
M_r = 913.98	Mo Kα radiation
Tetragonal, I4₁/acd	µ = 3.66 mm⁻¹
a = 15.1777 (4) Å	T = 100 K
c = 22.5094 (12) Å	0.44 × 0.44 × 0.18 mm
V = 5185.3 (3) Å³

Data collection top

Bruker SMART APEX CCD diffractometer	1997 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1775 reflections with I > 2σ(I)
T_min = 0.725, T_max = 1.000	R_int = 0.024
27002 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.092	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0554P)² + 37.1849P] where P = (F_o² + 2F_c²)/3
1997 reflections	Δρ_max = 3.41 e Å⁻³
110 parameters	Δρ_min = −1.62 e Å⁻³

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
Er1	0.5000	0.2500	0.3750	0.00421 (10)
Cl1	0.5000	0.2500	0.1250	0.0105 (3)
Cl2	0.72764 (5)	−0.02236 (5)	0.1250	0.0251 (2)
O1	0.59052 (11)	0.21840 (12)	0.29594 (8)	0.0150 (3)
O2	0.53202 (12)	0.39323 (11)	0.34440 (8)	0.0146 (3)
O3	0.57685 (14)	0.24307 (14)	0.16232 (9)	0.0230 (4)
O4	0.6459 (3)	−0.0156 (4)	0.1512 (3)	0.116 (2)
O5	0.7922 (3)	−0.0078 (3)	0.1690 (3)	0.0919 (17)
N1	0.66916 (14)	0.23390 (14)	0.27491 (9)	0.0130 (4)
N2	0.52617 (14)	0.44427 (13)	0.29795 (9)	0.0120 (4)
C1	0.70908 (16)	0.17164 (16)	0.24123 (10)	0.0142 (4)
H1	0.6810	0.1164	0.2351	0.017*
C2	0.78967 (15)	0.18759 (16)	0.21586 (11)	0.0140 (4)
H2	0.8168	0.1438	0.1918	0.017*
C3	0.52531 (17)	0.41139 (15)	0.24210 (10)	0.0138 (4)
H3	0.5249	0.3494	0.2361	0.017*
C4	0.52504 (17)	0.46718 (15)	0.19415 (10)	0.0142 (4)
H4	0.5240	0.4436	0.1551	0.017*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Er1	0.00435 (11)	0.00435 (11)	0.00392 (14)	−0.00025 (5)	0.000	0.000
Cl1	0.0123 (5)	0.0123 (5)	0.0067 (7)	0.000	0.000	0.000
Cl2	0.0235 (3)	0.0235 (3)	0.0283 (5)	−0.0089 (4)	0.0048 (2)	−0.0048 (2)
O1	0.0094 (7)	0.0220 (9)	0.0137 (7)	−0.0028 (6)	0.0040 (6)	−0.0033 (7)
O2	0.0220 (9)	0.0114 (7)	0.0105 (7)	−0.0015 (6)	−0.0032 (7)	0.0043 (6)
O3	0.0168 (9)	0.0376 (12)	0.0147 (9)	0.0044 (7)	−0.0043 (8)	−0.0022 (7)
O4	0.052 (3)	0.120 (4)	0.175 (5)	−0.003 (3)	0.075 (3)	0.000 (4)
O5	0.077 (3)	0.070 (3)	0.129 (5)	−0.002 (2)	−0.055 (3)	−0.029 (3)
N1	0.0110 (9)	0.0165 (9)	0.0113 (9)	−0.0011 (7)	0.0013 (7)	−0.0005 (8)
N2	0.0136 (9)	0.0107 (8)	0.0117 (9)	0.0001 (7)	−0.0016 (7)	0.0023 (7)
C1	0.0131 (10)	0.0149 (10)	0.0145 (10)	−0.0009 (8)	0.0016 (8)	−0.0019 (8)
C2	0.0122 (10)	0.0169 (11)	0.0128 (10)	−0.0003 (8)	0.0007 (8)	−0.0022 (8)
C3	0.0183 (11)	0.0105 (10)	0.0125 (10)	−0.0021 (8)	−0.0015 (9)	−0.0007 (8)
C4	0.0193 (11)	0.0115 (10)	0.0118 (10)	−0.0002 (8)	−0.0002 (9)	−0.0002 (8)

Geometric parameters (Å, º) top

Er1—O1ⁱ	2.2989 (17)	Cl2—O5^vi	1.410 (4)
Er1—O1ⁱⁱ	2.2989 (17)	O1—N1	1.305 (3)
Er1—O1	2.2989 (17)	O2—N2	1.304 (2)
Er1—O1ⁱⁱⁱ	2.2989 (17)	N1—C1	1.354 (3)
Er1—O2ⁱ	2.3316 (17)	N1—C2^vii	1.361 (3)
Er1—O2ⁱⁱ	2.3316 (17)	N2—C3	1.353 (3)
Er1—O2	2.3316 (17)	N2—C4^viii	1.356 (3)
Er1—O2ⁱⁱⁱ	2.3316 (17)	C1—C2	1.371 (3)
Cl1—O3	1.441 (2)	C1—H1	0.9500
Cl1—O3^iv	1.441 (2)	C2—N1^vii	1.361 (3)
Cl1—O3ⁱⁱⁱ	1.441 (2)	C2—H2	0.9500
Cl1—O3^v	1.441 (2)	C3—C4	1.372 (3)
Cl2—O4^vi	1.377 (4)	C3—H3	0.9500
Cl2—O4	1.377 (4)	C4—N2^viii	1.356 (3)
Cl2—O5	1.410 (4)	C4—H4	0.9500

O1ⁱ—Er1—O1ⁱⁱ	78.54 (9)	O3^iv—Cl1—O3ⁱⁱⁱ	109.86 (9)
O1ⁱ—Er1—O1	148.06 (9)	O3—Cl1—O3^v	109.86 (9)
O1ⁱⁱ—Er1—O1	110.48 (9)	O3^iv—Cl1—O3^v	108.69 (17)
O1ⁱ—Er1—O1ⁱⁱⁱ	110.48 (9)	O3ⁱⁱⁱ—Cl1—O3^v	109.86 (9)
O1ⁱⁱ—Er1—O1ⁱⁱⁱ	148.06 (9)	O4^vi—Cl2—O4	108.5 (5)
O1—Er1—O1ⁱⁱⁱ	78.55 (9)	O4^vi—Cl2—O5	113.0 (3)
O1ⁱ—Er1—O2ⁱ	80.86 (7)	O4—Cl2—O5	108.3 (4)
O1ⁱⁱ—Er1—O2ⁱ	72.63 (6)	O4^vi—Cl2—O5^vi	108.3 (4)
O1—Er1—O2ⁱ	73.44 (6)	O4—Cl2—O5^vi	113.0 (3)
O1ⁱⁱⁱ—Er1—O2ⁱ	137.94 (6)	O5—Cl2—O5^vi	105.9 (5)
O1ⁱ—Er1—O2ⁱⁱ	72.63 (6)	N1—O1—Er1	142.15 (15)
O1ⁱⁱ—Er1—O2ⁱⁱ	80.86 (7)	N2—O2—Er1	140.93 (15)
O1—Er1—O2ⁱⁱ	137.94 (6)	O1—N1—C1	119.1 (2)
O1ⁱⁱⁱ—Er1—O2ⁱⁱ	73.44 (6)	O1—N1—C2^vii	121.5 (2)
O2ⁱ—Er1—O2ⁱⁱ	145.63 (8)	C1—N1—C2^vii	119.4 (2)
O1ⁱ—Er1—O2	73.44 (6)	O2—N2—C3	121.8 (2)
O1ⁱⁱ—Er1—O2	137.94 (6)	O2—N2—C4^viii	119.0 (2)
O1—Er1—O2	80.86 (7)	C3—N2—C4^viii	119.2 (2)
O1ⁱⁱⁱ—Er1—O2	72.63 (6)	N1—C1—C2	120.6 (2)
O2ⁱ—Er1—O2	72.46 (9)	N1—C1—H1	119.7
O2ⁱⁱ—Er1—O2	118.42 (9)	C2—C1—H1	119.7
O1ⁱ—Er1—O2ⁱⁱⁱ	137.94 (6)	N1^vii—C2—C1	120.0 (2)
O1ⁱⁱ—Er1—O2ⁱⁱⁱ	73.44 (6)	N1^vii—C2—H2	120.0
O1—Er1—O2ⁱⁱⁱ	72.63 (6)	C1—C2—H2	120.0
O1ⁱⁱⁱ—Er1—O2ⁱⁱⁱ	80.87 (7)	N2—C3—C4	120.2 (2)
O2ⁱ—Er1—O2ⁱⁱⁱ	118.42 (9)	N2—C3—H3	119.9
O2ⁱⁱ—Er1—O2ⁱⁱⁱ	72.46 (9)	C4—C3—H3	119.9
O2—Er1—O2ⁱⁱⁱ	145.64 (8)	N2^viii—C4—C3	120.6 (2)
O3—Cl1—O3^iv	109.86 (9)	N2^viii—C4—H4	119.7
O3—Cl1—O3ⁱⁱⁱ	108.69 (17)	C3—C4—H4	119.7

Symmetry codes: (i) y+1/4, x−1/4, −z+3/4; (ii) −y+3/4, −x+3/4, −z+3/4; (iii) −x+1, −y+1/2, z; (iv) −y+3/4, x−1/4, −z+1/4; (v) y+1/4, −x+3/4, −z+1/4; (vi) y+3/4, x−3/4, −z+1/4; (vii) −x+3/2, −y+1/2, −z+1/2; (viii) x, −y+1, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O2^vii	0.95	2.50	3.266 (3)	138
C2—H2···O5	0.95	2.39	3.147 (5)	137
C3—H3···O1	0.95	2.60	3.321 (3)	133
C3—H3···O3	0.95	2.45	3.219 (3)	138
C4—H4···O3^iv	0.95	2.35	3.218 (3)	152

Symmetry codes: (iv) −y+3/4, x−1/4, −z+1/4; (vii) −x+3/2, −y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Er(C₄H₄N₂O₂)₄](ClO₄)₃
M_r	913.98
Crystal system, space group	Tetragonal, I4₁/acd
Temperature (K)	100
a, c (Å)	15.1777 (4), 22.5094 (12)
V (Å³)	5185.3 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	3.66
Crystal size (mm)	0.44 × 0.44 × 0.18

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.725, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	27002, 1997, 1775
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.092, 0.98
No. of reflections	1997
No. of parameters	110
H-atom treatment	H-atom parameters constrained
	w = 1/[σ²(F_o²) + (0.0554P)² + 37.1849P] where P = (F_o² + 2F_c²)/3
Δρ_max, Δρ_min (e Å⁻³)	3.41, −1.62

Computer programs: SMART (Bruker, 2007), SAINT-Plus (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O2ⁱ	0.95	2.50	3.266 (3)	137.8
C2—H2···O5	0.95	2.39	3.147 (5)	136.8
C3—H3···O1	0.95	2.60	3.321 (3)	132.8
C3—H3···O3	0.95	2.45	3.219 (3)	138.4
C4—H4···O3ⁱⁱ	0.95	2.35	3.218 (3)	152.3

Symmetry codes: (i) −x+3/2, −y+1/2, −z+1/2; (ii) −y+3/4, x−1/4, −z+1/4.

Acknowledgements

The authors are thankful to Allegheny College for providing funding in support of this research. The diffractometer was funded by the NSF (grant No. 0087210), the Ohio Board of Regents (grant No. CAP-491) and by Youngstown State University. The authors would like to acknowledge Youngstown State University and the STaRBURSTT CyberInstrumentation Consortium for assistance with the crystallography.

References

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