Synthesis and characterization of carbonate-encapsulated ytterbium- and yttrium-containing polyoxotungstates

Abstract

A sandwiched‐type carbonate‐encapsulated yttrium‐containing arsenotungstate(III) has been synthesized under mild reaction conditions. The polyanion [NaCH3COO{Y2(H2O)3(B‐α‐AsW9O33)2(W2O5)(CO3)}]12− (1) was isolated as a solid crystalline material by the reaction of a YIII salt with the sodium salt of trilacunary [AsW9O33]9− in sodium acetate solution. The sodium salt of the polyanion, i.e. Na12[Na(CH3COO){Y2(AsW9O33)2(W2O5)(CO3)(H3O)3}]·22H2O (1a), was characterized by various analytical techniques, such as FT–IR, single‐crystal X‐ray diffraction (SC–XRD), TGA (thermogravimetric analysis), 13C NMR and ESI–MS (electrospray ionization mass spectrometry). SC–XRD studies revealed that the polyanion crystallizes in the triclinic space group P. The structure showed that the polyanion is a carbonate‐encapsulated sandwich‐type species, consisting of two trilacunary B‐α‐[AsW9O33]9−, with a lone‐pair‐containing AsIII heteroatom, together with two extra tungsten centres and two yttrium cations at the sandwich position, where CH3COO− and Na+ ions act as linkers between the two polyanion units. In addition, we have also synthesized two carbonate‐encapsulated germanotungstates(IV), without lone‐pair‐containing heteroatoms, with the formula [Ln3(A‐β‐GeW9O34)2(CO3)(H2O)3]13− [Ln = YIII (2) and YbIII (3)], i.e. Y2K3Na4[Y3(A‐β‐GeW9O34)2(CO3)(H2O)3]·19H2O (2a) and YbK8Na2[Yb(A‐β‐GeW9O34)2(CO3)(H2O)3]·16H2O (3a), and characterized them by FT–IR, SC–XRD, TGA and ESI–MS. Here, the lanthanide ions act as linkers, extending the structures into higher dimensions. Sodium and potassium ions also play a key role as linkers, further extending the structure. The packing shows the presence of certain hydrophilic pores within the structure.

Syntheses, and Crystal Structures of YIII Containing Di‐Metal Substituted 1,5 Isomers of Heterometallic Tungstophosphate Nanoclusters: [Y{PM2W10O38(H2O)2}2]11– (M=CoII and ZnII)

“…Recently, in 2018, Hussain et al. have also reported a carbonate‐encapsulated yttrium (III)‐containing tungstoarsenate (III) along with two yttrium and ytterbium containing tungstogermanates …”

“…This hetero Keggin anion is found to be the mixture of isomers {( 1,2 ), ( 1,4 ), ( 1,5 ), ( 1,6 ) and ( 1,11 )} . It is not stable in aqueous solution which further leads to the formation of tetra‐metallic species [M 4 (OH 2 ) 2 (PW 9 O 34 ) 2 ] . This reaction was carried out in the presence of Y III ion, resulting in the formation of sandwiched complex.…”

Self‐Assembled Tetrameric Lanthanide‐Containing Germanotungstates [(Ln2GeW10O38)4(W3O8)(OH)4(H2O)2]26−: Syntheses, Crystal Structure, Photoluminescence and Electrochemical Properties.

“…The mixed sodium‐potassium salts of the polyanions 1 a ‐ 6 a obtained were then further characterized by FT‐IR spectroscopy, SC‐XRD, UV‐Vis spectroscopy, TGA, electrochemistry, ESI‐MS, PXRD and photoluminescence. We have also carried out the reactions with the remaining lanthanides under the same conditions but obtained carbonate encapsulated sandwiched compounds with Y III and Yb III which were published earlier . For the rest of the lanthanides, a precipitate was obtained.…”

“…The band at around 940 cm −1 is attributed to the asymmetric ν as (Ge‐O a ). The other three asymmetric vibration modes at around 852 cm −1 , 815 cm −1 and 680 cm −1 are attributed to ν as (W‐O t ) terminal, ν as (W‐O b ) corner sharing and ν as (W‐O c ) edge sharing vibrations, respectively …”

“…Recently, Hussain et al. have synthesized a carbonate‐encapsulated germanotungstate of the formula [Ln 3 (A‐β‐GeW 9 O 34 ) 2 (CO 3 )(H 2 O) 3 ] 13− with Ln=Y III and Yb III …”