Open AccessMagnetic Nature of the Cr III –Ln III Interactions in [Cr III 2 Ln III 3 ] Clusters with Slow Magnetic Relaxation
Author(s) -
Zhao XiaoQing,
Xiang Shuo,
Wang Jin,
Bao DongXu,
Li YunChun
Publication year - 2018
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.201700165
Subject(s) - diamagnetism , crystallography , ion , magnetic susceptibility , pivalic acid , chemistry , metal , trigonal bipyramidal molecular geometry , ferromagnetism , analytical chemistry (journal) , physics , crystal structure , magnetic field , condensed matter physics , organic chemistry , biochemistry , chromatography , quantum mechanics , catalysis
Abstract Two 3 d ‐4 f hetero‐metal pentanuclear complexes with the formula {[Cr III 2 Ln III 3 L 10 (OH) 6 (H 2 O) 2 ]Et 3 NH} [Ln=Tb ( 1 ), Dy ( 2 ); HL=pivalic acid, Et 3 N=triethylamine] have been produced. The metal core of each cluster is made up of a trigonal bipyramid with three Ln III ions (plane) and two Cr III ions (above and below) held together by six μ 3 ‐OH bridges. Also reported with this series is the diamagnetic Cr III –Y III analogue ( 3 ). Fortunately, we successfully prepared Al III –Ln III analogues with the formula {[Al III 2 Ln III 3 L 10 (OH) 6 (H 2 O) 2 ]Et 3 NH⋅H 2 O} [Ln=Tb ( 4 ), Dy ( 5 )], containing diamagnetic Al III ions, which can be used to evaluate the Cr III –Ln III magnetic nature through a diamagnetic substitution method. Subsequently, static (dc) magnetic susceptibility studies reveal dominant ferromagnetic interactions between Cr III and Ln III ions. Dynamic (ac) magnetic susceptibility studies show frequency‐dependent out‐of‐phase ( χ ′′) signals for [Cr III 2 Tb III 3 ] ( 1 ), [Cr III 2 Dy III 3 ] ( 2 ), and [Al III 2 Dy III 3 ] ( 5 ), which are derived from the single‐ion behavior of Ln III ions and/or the Cr III –Ln III ferromagnetic interactions.