Department of Chemistry, Korea University, Seoul 136-713, Korea.
Chemistry. 2011 Mar 1;17(10):3028-34. doi: 10.1002/chem.201002269. Epub 2011 Jan 31.
Three azide-bridged Mn(III) chains [Mn(3-MeOsalpn)(N(3))]⋅0.5 AClO(4) (A = Na (1), K (2), Rb (3); 3-MeOsalpn = N,N'-propylenebis(3-methoxysalicylideneiminato) dianion) incorporating alkali metal ions and perchlorate anions were systematically synthesized. The overall structure can be described as a one-dimensional chain bridged by end-to-end azide ligands, although spatial arrangements of Jahn-Teller axes of Mn in 1 and 2 are different from that in 3. Relying on the alkali metal ions, magnetic properties are varied from a two-step phase transition (1) to metamagnetic transitions (2 and 3). In this system, spin canting definitely plays a central role in giving rise to the apparent slow magnetic relaxations in 1 and 2 because application of a high external magnetic field tends to destroy single-chain magnet (SCM) properties. Despite the existence of a long-range antiferromagnetic order at T(N) , slow magnetic relaxation is notably observed in 2, which likely emanates from the operative spin canting below T(N) .
三个叠氮桥联的 Mn(III)链[Mn(3-MeOsalpn)(N(3))]⋅0.5 AClO(4)（A = Na（1），K（2），Rb（3）；3-MeOsalpn = N，N'-丙撑双（3-甲氧基水杨醛亚胺）二亚胺阴离子），其中包含碱金属离子和高氯酸盐阴离子，被系统地合成。整个结构可以描述为一维链，由端到端的叠氮配体桥接，尽管 1 和 2 中 Mn 的 Jahn-Teller 轴的空间排列与 3 不同。依赖于碱金属离子，磁性质从两步相变（1）到反铁磁转变（2 和 3）。在这个系统中，自旋倾斜肯定在导致 1 和 2 中出现明显的慢磁弛豫中起着核心作用，因为施加外部强磁场往往会破坏单链磁体（SCM）的性质。尽管在 T(N)存在长程反铁磁有序，但在 2 中明显观察到慢磁弛豫，这可能源自 T(N)以下的有效自旋倾斜。
