Crystal structure and spectroscopy of lanthanide complexes with glutaric acid [Ln(C5H6O4)(H2O)3] · ClO4

Synthesis, Characterisation and Luminescent Properties of Lanthanide‐Organic Polymers with Picolinic and Glutaric Acids

“…This is particularly notable for the bridging groups which appear as syn,anti bridges while in those related 1D compounds [12,13] one oxygen atom is simultaneously involved in a syn,syn chelate and in a syn,anti bridge. Moreover, this structural aspect exhibited by one carboxylato oxygen atom is repeatedly found in all the remaining known 2- [14] and 3D [15][16][17][18][19][20][21] lanthanide-organic materials containing glutaric acid residues, thus rendering the present compound the first example of a glutaratolanthanide material in which an inter-lanthanide bridge via a carboxylato group is enforced by a syn,anti bridge. Apart from structurally creating the aforementioned bimetallic units, the glutarato anionic residues further establish physi- (Figure 1, c and d).…”

“…On the other hand, the opposite carboxylato group, composed of O(3) and O(4) (Figure 1, a), appears instead forming a syn,anti bridge with a neighbouring Sm 3+ cation, thus imposing a Sm(1)···Sm (1) i separation of 4.626(1) Å. This syn,anti bridge leads to the formation of a centrosymmetric binuclear moiety which can be further envisaged as the building block of the polymeric structure of the material (see below), a structural feature only found in a handful of other structures also containing lanthanide centres and glutarato anions, namely with Nd 3+ , [12,13] Ho 3+ [13] and Tb 3+ , [14] all of which are 1D materials. Interestingly, in those compounds, the glutarato anions exhibit markedly distinct coordination geometries compared with those recorded for our material.…”

“…As reported by Zhang et al [13] for the 1D 2 ] molecular tape present in the crystal structure also contains, external to the glu/Sm core, chelating aromatic organic ligands (picolinato residues) which seem to prevent the growth of the hybrid polymer in more than one direction by removing available coordination sites in the metallic centres (Figure 1). Indeed for all known and related compounds, when these chelating moieties are not present, 2- [14] and 3D [15][16][17][18][19][20][21][22] materials are typically isolated. The picolinic acid residues appear coordinated to the Sm 3+ metallic centres in a typical N,O-chelating fashion (Scheme 1) with a bite angle of 64.97(10)°, a value consistent with those reported for similar compounds [23][24][25][26] (10 entries in the CSD, with values spanning from 60.5 to 67.6°; median of 64.0°).…”

“…On the one hand, strong and highly directional [all interaction angles Ͻ(DHA) are well above 150°-see Table 2] O-H···O hydrogen bonds involving the coordinated water molecules and the carboxylato groups interconnect neighbouring tapes in the bc plane of the unit cell leading to a 2D supramolecular framework (Figure 2, a). One of these interactions is particularly important for the structural integrity of the binuclear secondary building unit of the molecular tape, as represented in Figure 2 In fact, for all other closely related compounds, connections between adjacent lanthanide centres are usually assured by four carboxylato groups, either belonging to the glutarato [12][13][14]16,[18][19][20][21] or oxalato [15,17] anions in a pseudo-paddlewheel motif. For the ϱ 1 [Sm(glu)(pic)(H 2 O) 2 ] molecular tape, only two carboxylato groups bridge the metallic centres (Figure 2, b) with structural stability being achieved [a] (4) 172 (4) [a] Symmetry transformations used to generate equivalent atoms: Table 2.…”

Crystal structure of diaquadidysprosium triglutarate tetrahydrate, Dy2(H2O)2[O2C(CH2)3CO2]3 · 4H2O

“…Through O3, O6 and their symmetry related partners, the DyO9 polyhedra are edge-shared to generate 1D metal-oxygen chains extending in the [100] direction and the resulting chains are then bridged by the anti/gauche conformational glutarate anions into 2D brick-wall parallel to (001), which are further linked by the bischelating dicarboxylate anions to form 3D framework with the tunnels in the [100] direction filled with the lattice H2O molecules. The glutarate anions exhibit normal bonding values comparable with those reported in the literature [5][6][7]. …”