Syntheses and crystal structures of some new rare earth basic nitrates II: [Ln6O(OH)8(H2O)12(NO3)6](NO3)2·xH2O, Ln=Sm, Dy, Er; x(Sm)=6, x(Dy)=5, x(Er)=4

A New Series of Anhydrous Lanthanide‐Based Octahedral Hexanuclear Complexes

“…Through this synthetic method, numerous polymorphic phases of such hexanuclear lanthanide complexes have been obtained (Table 1). [14,33,34,36] From Table 1 it can be seen that several polymorphic phases can exist for a given lanthanide ion. Moreover, no hexanuclear, cerium-based complex has been reported so far despite the great potential application in heterogeneous catalysis.…”

Syntheses and crystal structures of rare earth basic nitrates hydrates

“…However, the type of clusters thus obtained can depend on the amino acid used and/or on the Ln metal itself. While l-tyrosine-controlled hydrolysis of Ln(ClO 4 ) 3 in the presence of halide ions (Ln = Eu, Nd, Gd, Pr) yielded pentadecanuclear Ln clusters with a halide anion in the middle of the cluster, the same procedure with Er(NO 3 ) 3 led to a formation of a well known octahedral cluster [Ln 6 ( 6 -O)( 3 -OH) 8 (H 2 O) 12 (2)(3) 6 ] [1a,c,2,3]. A hydrolysis of Nd and Gd perchlorates supported by l-serine led to a formation of new hydroxoclusters [Ln 6 ( 6 -O)( 3 -OH) 8 (H 2 O) 24 ] [4].…”

“…A second method of synthesis is based on a controlled hydrolysis of nitrates which yields the far most common hexanuclear octahedral clusters [Ln 6 ( 6 -O)( 3 -OH) 8 (H 2 O) 12 ( 2 -NO 3 ) 6 ] 2+ [2,3,8]. This can be performed either by a careful increase of pH by an addition of diluted NaOH to Ln(NO 3 ) 3 solution [8,10] or by a spontaneous hydrolysis of the solution of the first hydrolytical product of thermally decomposed Ln(NO 3 ) 3 in the solution of appropriate Ln nitrate [2,3,18,19].…”

“…This can be performed either by a careful increase of pH by an addition of diluted NaOH to Ln(NO 3 ) 3 solution [8,10] or by a spontaneous hydrolysis of the solution of the first hydrolytical product of thermally decomposed Ln(NO 3 ) 3 in the solution of appropriate Ln nitrate [2,3,18,19]. Recently, two papers dealing with the synthesis of Pr and Nd octahedral complex salts with the formula Ln 6 ( 6 -O)( 3 -OH) 8 3 in the presence of di-thienyl ketone [9], the paper [10] describes the synthesis of Pr and Nd salts of the same formula by a controlled hydrolysis of Ln(NO 3 ) 3 with diluted solution of NaOH.…”

“…In two previous papers [2,3] we have described the synthesis and crystal structures of six new rare earth basic nitrate hydrates (LnBN), namely those of Y, Sm, Gd, Dy, Er, and Yb. Extending these investigations, however, we have also managed to prepare representatives of some more rare earth elements by varying the conditions of crystallization (especially temperature and concentration of Ln(NO 3 ) 3 in the solution), and we were also successful to obtain several different phases differing by their number of noncoordinated H 2 O molecules for the same rare earth element.…”