Poly[μ3-acetato-di-μ3-isonicotinato-μ2-isonicotinato-samarium(III)silver(I)]

Li-Cai Zhu

doi:10.1107/S1600536809048430

. 2009 Nov 21;65(Pt 12):m1616. doi: 10.1107/S1600536809048430

Poly[μ₃-acetato-di-μ₃-isonicotinato-μ₂-isonicotinato-samarium(III)silver(I)]

Li-Cai Zhu ^a,^*

PMCID: PMC2972026 PMID: 21578640

Abstract

In the title homochiral three-dimensional heterometallic complex, [AgSm(C₆H₄NO₂)₃(C₂H₃O₂)]_n, the eight-coordinate Sm^III ion displays a bicapped trigonal-prismatic geometry, being coordinated by two O atoms from one acetate ligand, four O atoms from four bridging isonicotinate ligands and two O atoms from two terminal isonicotinate ligands. The four-coordinate Ag^I ion adopts a tetrahedral geometry, being bonded to two N atoms from two bridging isonicotinate ligands and two O atoms from two acetate ligands. These metal coordination units are connected by bridging isonicotinate and acetate ligands, generating a three-dimensional network.

Related literature

For the applications of lanthanide–transition metal heterometallic complexes with bridging multifunctional organic ligands in ion exchange, magnetism, bimetallic catalysis and as luminescent probes, see: Cheng et al. (2006 ▶); Gu & Xue (2006 ▶); Peng et al. (2008 ▶); Zhu et al. (2009 ▶). graphic file with name e-65-m1616-scheme1.jpg

Experimental

Crystal data

[AgSm(C₆H₄NO₂)₃(C₂H₃O₂)]
M _r = 683.58
Hexagonal,
a = 11.8184 (5) Å
c = 27.340 (2) Å
V = 3307.0 (3) Å³
Z = 6
Mo Kα radiation
μ = 3.58 mm⁻¹
T = 296 K
0.23 × 0.20 × 0.19 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.444, T _max = 0.507
17136 measured reflections
1992 independent reflections
1928 reflections with I > 2σ(I)
R _int = 0.046

Refinement

R[F ² > 2σ(F ²)] = 0.020
wR(F ²) = 0.049
S = 1.06
1992 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.65 e Å⁻³
Δρ_min = −0.45 e Å⁻³
Absolute structure: Flack (1983 ▶), 739 Friedel pairs
Flack parameter: 0.006 (15)

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809048430/pv2235sup1.cif

e-65-m1616-sup1.cif^{(17.3KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809048430/pv2235Isup2.hkl

e-65-m1616-Isup2.hkl^{(98.2KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The author acknowledges South China Normal University for supporting this work.

supplementary crystallographic information

Comment

In the past few years, lanthanide-transition metal heterometallic complexs with bridging multifunctionnal organic ligands are of increasing interest, not only because of their impressive topological structures, but also due to their versatile applications in ion exchange, magnetism, bimetallic catalysis and luminescent probe (Cheng et al., 2006; Peng et al., 2008; Zhu et al., 2009). However, because of complicated interactions among the organic moiety and two types of metal centers, the construction of a homochiral Ln—M heterometallic coordination framework is one of the most challenging issues in synthetic chemistry and materials science(Gu & Xue, 2006). As an extension of this research, the structure of the title compound, a new homochiral heterometallic coordination polymer, (I), has been determined which is presented in this article.

In the title compound (Fig. 1), there are half of Sm^III ion, half of Ag^I ion, half of acetate ligand, and one and half crystallogaphically unique isonicotinate ligands in the asymmetrical unit. Isonicotinate ligands have two types of distinctly different coordination modes: one acts as a bridging ligand to coordinate one Ag^I ion and two Sm^III ions, and the other acts as a terminal ligand to coordinate two Sm^III ions. Acetate ligand adopts chelating [Sm^III] and bridging [Ag^I] coordination modes. Each Sm^III ion is eight-coordinated by two O atoms from one acetate ligand, four O atoms from four bridging isonicotinate ligands, and two O atom from two terminal isonicotinate ligands. The Sm center can be described as having a bicapped trigonal prism coordination geometry. The four-coordinated Ag^I ion is bonded to two N atoms from two bridging isonicotinate ligand and two O atoms from two acetate ligands to furnish a tetrahedral geometry, (Table 1). These metal coordination units are connected by bridging isonicotinate and acetate ligands, generating a three-dimensional network (Fig. 2).

Experimental

A mixture of AgNO₃(0.057 g, 0.33 mmol), Sm₂O₃(0.116 g, 0.33 mmol), isonicotinic acid (0.164 g, 1.33 mmol), acetic acid (0.080 g, 1.33 mmol), and H₂O(7 ml) was sealed in a 20 ml Teflon-lined reaction vessel at 443 K for 6 days then slowly cooled to room temperature. The product was collected by filtration, washed with water and air-dried. Colorless block crystals suitable for X-ray analysis were obtained.