Crystal structures, single‐molecule magnetic behavior, and ab initio calculations of four new phenoxo‐bridged dinuclear dysprosium complexes and their gadolinium(III) analogues are explored. Complexes [Dy₂(DMOMP)₂(DBM)₄]₂⋅CHCl₃ (1; DMOMP=1‐methyl‐3,5‐dimethoxy‐4‐hydroxybenzene, DBM=1,3‐diphenylpropane‐1,3‐dione); [Dy₂(DMOAP)₂(DBM)₄]₂⋅CHCl₃ (2; DMOAP=syringaldehyde); Dy₂(DMOEP)₂(DBM)₄ (3; DMOEP=methyl syringate); and solvent‐free Dy₂(DMOMP)₂(DBM)₄ (4), which is obtained by the transformation of single crystal into single crystal from 1, have nearly identical core structures and only differ in the substituents at the para position of the phenol moieties of the bridging ligand. In this system, the electronic effects are efficiently implemented to significantly modify the ligand field strength and exchange coupling by modulating the substituents on the phenol backbone. The effective energy barrier (U_eff) of magnetization reversal is improved significantly to fivefold magnitude, at most, and the hysteresis temperature up to 3.5 K by deliberately using the electron‐withdrawing substituent to replace the electron‐donating one. The origin of the two relaxation processes in 1 is mostly attributed to the existence of two molecules in one unit, which is illuminated by means of the transformation of single crystal into single crystal.

中文翻译：

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双核Dy2单分子磁体：单晶至单晶系统中桥联配体的功能调制和不同的弛豫性能

探索了四种新的苯氧桥双核dy络合物及其their（III）类似物的晶体结构，单分子磁行为和从头算。配合物[镝₂（DMOMP）₂（DBM）₄ ] ₂ ⋅氯仿₃（1 ; DMOMP = 1-甲基-3,5-二甲氧基-4-羟基苯，DBM = 1,3-二苯基丙烷-1,3-二酮） ; [Dy ₂（DMOAP）₂（DBM）₄ ] ₂ · CHCl ₃（2； DMOAP =丁醛）；Dy ₂（DMOEP）₂（DBM）₄（3; DMOEP =丁香酸甲酯）; 无溶剂的Dy ₂（DMOMP）₂（DBM）₄（4），是通过将单晶从1转变为单晶而获得的，它们的核结构几乎相同，只是取代基的对位不同桥接配体的苯酚部分。在该系统中，通过调节酚主链上的取代基，可以有效地实现电子效应，从而显着改变配体场强和交换耦合。有效能垒（U _eff）故意使用吸电子取代基代替给电子基团，磁化反转最多可显着提高到五倍，磁滞温度最高可达3.5K。1中的两个弛豫过程的起源主要归因于一个单元中存在两个分子，这是通过将单晶转变为单晶来阐明的。