Octanuclear Ni4Ln4 Coordination Aggregates from Schiff Base Anion Supports and Connecting of Two Ni2Ln2 Cubes: Syntheses, Structures, and Magnetic Properties

Abstract A family of 3d–4f aggregates have been reported through guiding the dual coordination modes of ligand anion (HL − ) and in situ generated ancillary bridge driven self‐assembly coordination responses toward two different types of metal ions. Reactions of lanthanide(III) nitrate (Ln=Gd, Tb, Dy, Ho and Yb), nickel(II) acetate and phenol‐based ditopic ligand anion of 2‐[{(2‐hydroxypropyl)imino}methyl]‐6‐methoxyphenol (H 2 L) in MeCN‐MeOH (3 : 1) mixture and LiOH provided five new octanuclear Ni‐4f coordination aggregates from two Ni 2 Ln 2 cubanes. Single‐crystal X‐ray diffraction analysis reveals that all the members of the family are isostructural, with the central core formed from the coupling of two distorted [Ni 2 Ln 2 O 4 ] heterometallic cubanes [Ni 2 Ln 2 (HL) 2 ( μ 3 ‐OH) 2 (OH)(OAc) 4 ] + (Ln=Gd ( 1 ), Tb ( 2 ), Dy ( 3 ), Ho ( 4 ) and Yb ( 5 )). Higher coordination demand of 4f ions induced the coupling of the two cubes by (OH)(OAc) 2 bridges. Variable temperature magnetic study reveals weak coupling between the Ni 2+ and Ln 3+ ions. For the Tb ( 2 ) and Dy ( 3 ) analogs, the compounds are SMMs without an applied dc field, whereas the Gd ( 1 ) analogue is not an SMM. The observation revealed thus that the anisotropy of the Ln 3+ ions is central to display the SMM behavior within this structurally intriguing family of compounds.