Synthesis, Structural Characterization, and Luminescence Properties of Lanthanide Oxalatophosphonates:  Na[M₃(H₂O)₄(C₂O₄)₄(CH₃PO₃)]·2H₂O (M = Nd and Pr)

Abstract

A neodymium oxalatophosphonate and its praseodymium analogue, Na[Nd3(H2O)4(C2O4)4(CH3PO3)]·2H2O and Na[Pr3(H2O)4(C2O4)4(CH3PO3)]·2H2O, have been synthesized by a hydrothermal method and characterized by single-crystal X-ray diffraction and thermogravimetric analysis. We studied the photoluminescence spectra of the Nd and Pr compounds as well as the magnetic properties of the Nd compound. The structure consists of layers built of tetramers of edge- and face-sharing NdO9 (or PrO9) polyhedra connected by oxalate and methylphosphonate units, which are linked by zigzag infinite chains of oxalate-bridged NdO9 (or PrO9) polyhedra to form a 3D framework. They are the first examples of lanthanide oxalate-methylphosphonate. The Nd compound displays characteristic emission bands in the near IR region. The χM T value decreases from 1.68 cm3 K/mol Nd at 300 K to 0.659 cm3 K/mol Nd at 2 K. The value at room temperature is close to the theoretical value for a mononuclear Nd3+ species. Luminescence of the Pr compound consists of many emission bands at 480−760 nm. The lifetimes of both compounds are much shorter than the expected values because of the quenching effects of water molecules in the structure. Crystal data for the Nd compound: triclinic, P1̄ (No. 2), a = 9.0682(2) Å, b = 9.5114(3) Å, c = 14.0066(4) Å, α = 74.975(2)°, β = 86.534(2)°, γ = 82.725(2)°, and Z = 2. Crystal data for the Pr compound are the same as those for the Nd compound, except a = 9.125(1) Å, b = 9.549(1) Å, c = 14.073(2) Å, α = 75.086(2)°, β = 86.611(2)°, and γ = 82.545(2)°.

Hydrothermal synthesis and structural characterization of ammonium ion-templated lanthanide(III) carboxylate-phosphonates

“…The P-C distance is 1.791(14) Å. These distances are in good agreement with similar compounds in the literature (Legendziewicz et al, 1998; Serre et al, 2004; Song and Mao, 2005; Tang et al, 2006a; Ying and Mao, 2006; Huang et al, 2007; Liu et al, 2007; Mao, 2007). …”

“…The design and syntheses of porous lanthanide phosphonates are attractive in developing new materials with multifunctions (Song and Mao, 2005; Ying and Mao, 2006; Liu et al, 2007; Mao, 2007). The successful synthesis of the first open-framework lanthanide carboxyphosphonate Pr 4 (H 2 O) 7 (O 3 PCH 2 NC 5 H 9 COO) 4 (H 2 O), opened the way for a number of other lanthanide hybrid solids to be isolated (Massiot et al, 1997; Legendziewicz et al, 1998; Serre et al, 2004; Bauer et al, 2006; Tang et al, 2006a,b; Huang et al, 2007; Zhou et al, 2010). For example, using lanthanide chlorides and N -(carboxymethyl)iminodi(methylphosphonic acid)(H 5 cmp) a series of layered [Ln(H 2 cmp)(H 2 O)] materials [where Ln 3+ = Y 3+ , La 3+ , Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Gd 3+ , Tb 3+ , Dy 3+ , Ho 3+ , and Er 3+ ], and the mixed-lanthanide [(Gd 0.95 Eu 0.05 )(H 2 cmp)(H 2 O)] material, have been successfully isolated from hydrothermal synthesis as phase-pure micro-crystalline compounds, (Cunha-Silva et al, 2009) and found to be supramolecular polymorphs of the compound that was reported by Mao and co-workers (Massiot et al, 1997; Bauer et al, 2006; Tang et al, 2006b; Zhou et al, 2010).…”

A multicolor persistent luminescent phosphor Sr2Ga2GeO7:Pr3+ for dynamic anticounterfeiting

“…It is observed in Figure 3A that the typical Sr 2 Ga 2 GeO 7 :0.2mol%Pr 3+ sample shows characteristic emission lines in the range 450-800 nm when excited at 254 nm, which are due to the f-f transitions of Pr 3+ . 19 Particularly, the blue emissions at around 492 nm is attributed to the 3 P 0 → 3 H 4 transition and the red emission at 614 nm is ascribed to the 1 D 2 → 3 H 4 transition as shown in Figure 3B. 20 Figure 3C presents the normalized PL spectra (λ ex = 254 nm) of all Sr 2 Ga 2 GeO 7 :x%Pr 3+ samples.…”

Two bicyclic dinuclear complexes generated from 3,3′-[1,3,4-thiadiazole-2,5-diyldi(thiomethylene)]dibenzoic acid (L) and dimethylformamide (DMF): [Cu(L)(DMF)]2and [Zn(L)(DMF)]2

“…Supramolecular chemistry has developed dramatically over recent decades. Numerous organometallic complexes have been designed for a number of potential applications, such as in synthetic chemistry (Sommerfeldt et al, 2008), in gas storage (Rowsell & Yaghi, 2005;Ma & Zhou, 2006), in selective absorption (Dong, Zhang et al, 2007), as luminescence materials (Wang, Ma et al, 2007;Huang et al, 2007) and as magnetic materials (Halder et al, 2002;Neville et al, 2008). Although the principles for controlling the solid structures of the target products still need to be classified and established, many rational synthetic strategies have been put forward (Dong, Jiang et al, 2007;Zhang et al, 2008).…”