title: Near-IR luminescence and field-induced single molecule magnet of four salen-type ytterbium complexes.
abstract: A series of rigid hexadentate salen-type (H2L) ytterbium complexes, namely, [Yb2L3(CH3OH)]·3CH3CN (1), [Yb2LL'L″(CH3OH)(H2O)2](ClO4)2·CH3OH·H2O (2), [Yb2L(OAc)4(CH3OH)2]·2CH3OH (3), and {[Yb2L(OAc)4]·3H2O}n (4) (H2L = N,N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine, HL' = 2-(2'-hydroxy-3'-methyloxy-phenyl)benzimidazole and HL" = 3-methoxysalicylaldehyde) have been synthesized by reactions of H2L with multifarious Yb(3+) salts. X-ray crystallographic analyses demonstrate that complex 1 is of a triple-decker sandwich-type Yb2L3 structure with a ratio of H2L/Yb = 3:2, 2 and 3 possess the unique Yb2 core with a ratio of H2L/Yb = 2:2 and 1:2, respectively, 4 exhibits one dimensional coordination polymers in which the polymeric structures are formed by acetate (OAc(-)) groups. All complexes 1-4 exhibit near-IR luminescence, which can be rationalized on the basis of the disparate structural effects. The magnetic analysis unveils that all complexes 1-4 are of field-induced single-molecule magnet behavior with the energy barriers (Ueff/kB) of 14.5, 2.0, 9.5, and 2.4 K at 3 kOe direct current fields, respectively.
authors.affiliation: Key Laboratory of Functional Inorganic Material Chemistry (MOE); School of Chemistry and Materials Science, Heilongjiang University , Harbin 150080, P. R. China.
authors.forename: Tian-Qi
authors.initials: TQ
authors.lastname: Liu
authors.forename: Peng-Fei
authors.initials: PF
authors.lastname: Yan
authors.forename: Fang
authors.initials: F
authors.lastname: Luan
authors.forename: Yu-Xin
authors.initials: YX
authors.lastname: Li
authors.forename: Jing-Wen
authors.initials: JW
authors.lastname: Sun
authors.forename: Chuan
authors.initials: C
authors.lastname: Chen
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Han
authors.initials: H
authors.lastname: Chen
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Zou
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Li