catena-Poly[[tetra­kis(hexa­methyl­phospho­ramide-κO)bis­(nitrato-κ2 O,O′)lanthanum(III)] [silver(I)-di-μ2-sulfido-tungstate(VI)-di-μ2-sulfido]]

Guodong Tang; Jinfang Zhang; Chi Zhang; Lude Lu

doi:10.1107/S1600536807066597

. 2008 Jan 23;64(Pt 2):m399–m400. doi: 10.1107/S1600536807066597

catena-Poly[[tetrakis(hexamethylphosphoramide-κO)bis(nitrato-κ² O,O′)lanthanum(III)] [silver(I)-di-μ₂-sulfido-tungstate(VI)-di-μ₂-sulfido]]

Guodong Tang ^a,^b, Jinfang Zhang ^a, Chi Zhang ^a,^*, Lude Lu ^a

PMCID: PMC2960413 PMID: 21201349

Abstract

Hexamethylphosphoramide (hmp), tetrathiotungstate(VI), silver sulfide and lanthanum(III) nitrate are self-assembled to form discrete cations one-dimensional poylmeric anionic chains [AgWS₄]_nⁿ ⁻ in the title compound, {[La(NO₃)₂(C₆H₁₈N₃OP)₄][AgWS₄]}_n. The central La atom in the cation is coordinated by eight O atoms from two nitrate and four hmp ligands. Together with the two nitrate ligands, the cation is monovalent, which leads to the anionic chain having a monovalent repeat unit. The polymeric anionic chain with W⋯Ag⋯W and Ag⋯W⋯Ag angles of 165.94 (3) and 155.894 (14)° presents a distorted linear configuration. Five N atoms, 18 C atoms and their attached H atoms are disordered equally over two positions.

Related literature

The one-dimensional W/S/Ag anionic polymers {(γ-MePyH)[WS₄Ag]}_n (Lang et al., 1993 ▶) and {[NH₃C(CH₂OH)₃][WS₄Ag](2DMF)}_n (Huang et al., 1997 ▶) have ideal and nearly linear configurations, respectively. Two analogs of the title compound, {[Eu(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Qian et al., 2007 ▶) and {[Y(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Cao et al., 2007 ▶), have similar wave-like chains. {[Nd(dmf)₈][W₄S₁₆Ag₅]}_n (Huang et al., 1996 ▶) has solvent-coordinated rare-earth cations leading to an anionic chain with a trivalent repeat unit. For a review of polymeric Mo(W)/S/Ag(Cu) clusters, see: Niu et al. (2004 ▶). For a review of the third-order non-linear optical properties of Mo(W)/S/Ag(Cu) clusters, see: Zhang, Song et al. (2007 ▶).

Experimental

Crystal data

[La(NO₃)₂(C₆H₁₈N₃OP)₄][AgWS₄]
M _r = 1399.71
Monoclinic,
a = 15.883 (2) Å
b = 30.070 (4) Å
c = 11.5283 (15) Å
β = 90.502 (3)°
V = 5505.8 (12) Å³
Z = 4
Mo Kα radiation
μ = 3.52 mm⁻¹
T = 295 (2) K
0.50 × 0.42 × 0.38 mm

Data collection

Rigaku Mercury diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.18, T _max = 0.26
50056 measured reflections
10031 independent reflections
8984 reflections with I > 2σ(I)
R _int = 0.049

Refinement

R[F ² > 2σ(F ²)] = 0.059
wR(F ²) = 0.137
S = 1.15
10031 reflections
462 parameters
32 restraints
H-atom parameters constrained
Δρ_max = 1.07 e Å⁻³
Δρ_min = −1.90 e Å⁻³

Data collection: CrystalClear (Rigaku, 2000 ▶); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku/MSC, 2002 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 ▶); molecular graphics: SHELXL97; software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536807066597/hg2364sup1.cif

e-64-0m399-sup1.cif^{(44.7KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807066597/hg2364Isup2.hkl

e-64-0m399-Isup2.hkl^{(490.5KB, hkl)}

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

Acknowledgments

This work is supported by the National Natural Science Foundation of China (No. 50472048) and the Program for New Century Excellent Talents in Universities (NCET-05-0499).

supplementary crystallographic information

Comment

One-dimensional Mo(W)/S/Ag anionic polymers have attracted much attention for their configurational isomerism (Niu et al., 2004) and unique properties as functional materials, such as third-order nonlinear optical (NLO) materials (Zhang, Song et al., 2007, and references therein). Different solvent-coordinated rare-earth cations proved effective to obtain various configurations of anionic chains (Niu et al., 2004). The title compound {[La(hmp)₄(NO₃)₂][WS₄Ag]}_n (hmp = hexamethylphosphoramide) with a wave-like anionic chain was prepared by following such route using La(III)-hmp complex as counterion.

The cation in the title compound, where La^3- is coordinated by eight O atoms from two nitrate and four hmp ligands, has the same structure as those in the isostructural {[Eu(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Qian et al., 2007) and {[Y(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Cao et al., 2007). Parts of dimethylamine groups from hmp ligands have large librations, which gives rise to some disordered C and N atoms. In possession of two nitrate ligands, the cation in the title compound is univalent (Fig. 1), which leads to an anionic chain with a univalent repeat unit, unlike other solvent-coordinated rare-earth cations (Niu et al., 2004, and references therein), which are trivalent and induce trivalent repeat units. For example, [Nd(dmf)₈]³⁺ induces an anionic chain with a trivalent repeat unit [W₄S₁₆Ag₅]^3- (Huang et al., 1996).

As illustrated in Fig. 2, the anionic chain in the title compound has a distorted linear configuration with W—Ag—W and Ag—W—Ag angles of 165.94 (3) and 155.894 (14) °, unlike those in {(γ-MePyH)[WS₄Ag]}_n (Lang et al. 1993) and {[NH₃C(CH₂OH)₃][WS₄Ag](2DMF)}_n (Huang et al., 1997), showing an ideal linear chain and a nearly linear chain, respectively. This fact suggests that cations with bigger bulk lead to more distorted anionic chains.

Similar angles for W—Ag—W and Ag—W—Ag are found in another two distorted linear chains in {[Eu(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Qian et al., 2007) and {[Y(hmp)₄(NO₃)₂][WS₄Ag]}_n (Zhang, Cao et al., 2007), implying that different rare earth cations with the same coordination environments will result in the same anionic structures.

Experimental

1 mmol A g₂S was added to a solution of [NH₄]₂WS₄ (2 mmol in 30 mL h mp) with thorough stirring for 9 h. The solution underwent an additional stir for one minute after 1 mmol La(NO₃)₃.6H₂O was added. After filtration the orange-red filtrate was carefully laid on the surface with 30 ml i-PrOH. Orange-red block crystals were obtained after ten days. Yield: 1.302 g in pure form, 46.5% (based on W). Analysis calculated for C₂₄H₇₂AgLaN₁₄O₁₀P₄S₄W: C 20.59, H 5.18, N 14.01%; found: C 20.57, H 5.15, N 14.03%. IR: ν, cm^-1, 482.9 m, 446.8 s (W-µ₂-S).