CAJ | 학술논문

结合对称性破损(BS)方法,采用不同的密度泛函理论(DFT)对反铁磁性μ-1,3-N3-Ni(II)叠氮配合物[LNi2(N3)](ClO4)2(L=pyrazolate)的磁特性进行了研究.结果显示,杂化密度泛函理论(HDFT)的计算结果与实验数据非常吻合,能够准确描述配合物的磁特性.磁轨道研究结果表明,配合物表现出较大的单占据轨道能量劈裂(0.93-0.99 eV),显示配合物的单占据轨道去简并化程度较大,且配合物中的2个磁通道(叠氮基、配体pyrazolate)中都分别存在有氮原子之间的p轨道重叠,这些都使得体系表现为反铁磁耦合作用.另外,配合物的磁性与叠氮桥和两金属离子间形成的二面角(τ, Ni-N-N-N-Ni)密切相关,τ从-55.38°逐渐变化到-1.5°的过程中,其反铁磁性逐渐增强,交换耦合常数(Jab)的绝对值逐渐增大,并在-11.95°处达到最大值(Jab=-151.02 cm-1).在此过程中,配合物中叠氮桥及其所连接的2个Ni离子与pyrazolate基配体L-中的2个桥原子N(4)、N(5)形成的七元环共平面性不断增强,即共平面性会诱导增强体系的反铁磁相互作用.
결합대칭성파손(BS)방법,채용불동적밀도범함이론(DFT)대반철자성μ-1,3-N3-Ni(II)첩담배합물[LNi2(N3)](ClO4)2(L=pyrazolate)적자특성진행료연구.결과현시,잡화밀도범함이론(HDFT)적계산결과여실험수거비상문합,능구준학묘술배합물적자특성.자궤도연구결과표명,배합물표현출교대적단점거궤도능량벽렬(0.93-0.99 eV),현시배합물적단점거궤도거간병화정도교대,차배합물중적2개자통도(첩담기、배체pyrazolate)중도분별존재유담원자지간적p궤도중첩,저사도사득체계표현위반철자우합작용.령외,배합물적자성여첩담교화량금속리자간형성적이면각(τ, Ni-N-N-N-Ni)밀절상관,τ종-55.38°축점변화도-1.5°적과정중,기반철자성축점증강,교환우합상수(Jab)적절대치축점증대,병재-11.95°처체도최대치(Jab=-151.02 cm-1).재차과정중,배합물중첩담교급기소련접적2개Ni리자여pyrazolate기배체L-중적2개교원자N(4)、N(5)형성적칠원배공평면성불단증강,즉공평면성회유도증강체계적반철자상호작용.
The magnetic properties of the antiferromagnetic complexμ-1,3-N3-Ni(II)[LNi2(N3)](ClO4)2 (L=pyrazolate) were investigated using density functional theory (DFT) calculations combined with the broken symmetry approach. The calculation results obtained using the hybrid density functional theory (HDFT) agree wel with the experimental data, and accurately describe the magnetic properties of complex. The large energy splitting, 0.93-0.99 eV, between singly occupied molecular orbitals indicates that there is strong non-degeneracy between them, and the two coupling paths (azido and pyrazolate) in the complex show that there is overlap between the p orbitals of the N atoms. Al these factors contribute to the antiferromagnetism of the complex. The magnetic properties of the complex are also closely related to the dihedral angleτof Ni-N-N-N-Ni. The antiferromagnetism of the complex increases asτdecreases from-55.38° to-1.5°;the maximum absolute value of magnetic coupling constant (Jab) occurs at-11.95° (Jab=-151.02 cm-1). During this process, the coplanarity of the seven-membered ring, which consists of two Ni(II), one azido, and two bridging nitrogen atoms (N(4) and N(5)), is enhanced, i.e., coplanarity increases the antiferromagnetism of the complex.