Field-induced slow magnetic relaxation in two-dimensional and three-dimensional Co(ii) coordination polymers

Deyun Ma; Guo Peng; Ying-Ying Zhang; Bo Li

doi:10.1039/c9dt02070e

Field-induced slow magnetic relaxation in two-dimensional and three-dimensional Co(ii) coordination polymers

Dalton Trans. 2019 Nov 7;48(41):15529-15536. doi: 10.1039/c9dt02070e. Epub 2019 Jul 17.

Authors

Deyun Ma¹, Guo Peng², Ying-Ying Zhang³, Bo Li⁴

Affiliations

¹ School of Food and Pharmaceutical Engineering, Zhaoqing University, Zhaoqing 526061, P. R. China.
² College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China. guopeng@njtech.edu.cn and Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China. guopeng@njust.edu.cn.
³ Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China. guopeng@njust.edu.cn.
⁴ College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061, P. R. China. libozzu0107@163.com.

PMID: 31314024
DOI: 10.1039/c9dt02070e

Abstract

Two coordination polymers formulated as [Co(1,4-bimb)_0.5(5-aip)(H₂O)]_n (1) and [Co(1,4-bib)_1.5(5-hip)(H₂O)]_n (2) (1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 5-aip = 5-aminoisophthalic acid, 1,4-bib = 1,4-bis(1-imidazolyl)benzene and 5-hip = 5-hydroxyisophthalic acid) have been prepared and structurally characterized. Complex 1 is a two-dimensional (2D) network where Co(ii) is six coordinate in a CoO₄N₂ coordination environment, while the structure of 2 consists of a three-dimensional (3D) framework built from mononuclear Co(ii) units with distorted octahedral geometry as nodes. Static magnetic studies show that first-order orbital angular momentum may play an important role in the magnetic properties of 1, whereas strong easy-axis anisotropy (D = -102 cm^-1) was observed in 2. Alternating current (ac) susceptibility measurements demonstrate that both the complexes display field-induced single ion magnet (SIM) behavior.