| The molecular magnetic material refers to magnetic complex which is synthesized by the reaction of paramagnetic ions or free radicals and anti-magnetic ligands in a method of molecular chemical synthesis with the structure of supramolecular chemistry and molecular magnetic exchange properties.Due to its excellent properties such as insulation,low density,high strength,good light transmission,easy processing,and strong plasticity,these materials are favored by researchers.In recent years,the study of 3d metal magnetic complexes is particularly important with the in-depth study of molecular-based magnetic materials by a large number of scientific researchers.In this dissertation,we choose suitable 3d metal ions and various cyanide precursors to study their reaction under different conditions,resulting in some new magnetic complexes structurally characterized and magnetically investigated.The main research contents are as follows:1.Two mononuclear seven-coordinated macrocycle manganese(?)compounds and four polycyanometallates containing different cyanide groups have been employed as building blocks to assemble cyanide-bridged heterobimetallic complexes,resulting in eight cyanide-bridged Fe?/?-Mn?and MIV-Mn?(M=Mo,W)complexes{[Mn(L1)][Fe(1-Me Im)(CN)5]}n(1){[Mn(L2)(H2O)][Fe(1-Me Im)(CN)5]}·2H2O(2){[Mn(L1)(H2O)][Mn(L1)][Fe(CN)6]}n·n(CH4O)·3.5n H2O(3){[Mn(L2)(H2O)]2[Fe(CN)6]}·11H2O(4){[Mn(L1)(H2O)][Mn(L1)][Mo(CN)8]}n·4n H2O(5){[Mn(L2)(H2O)]2[Mo(CN)8]}·3.5H2O(6){[Mn(L1)(H2O)][Mn(L1)][W(CN)8]}n·5n H2O(7){[Mn(L2)(H2O)]2[W(CN)8]}·3H2O(8)(L1=3,6-diazaoctane-1,8-diamine,L2=3,6-dioxaoctano-1,8-diamine).Single X-ray analysis reveals that complexes 1,3,5,and 7 obtained by using[Mn(L1)]2+as assemble segment can be structurally characterized as a one-dimensional coordination polymer,while the structures of the complexes 2,4,6 and 8 with[Mn(L2)]2+as the ancillary compound belong to polynuclear entities,indicating that the different coordination field of the N atom or the O atom in the macrocyclic ligands can have an obvious influence on the structure types of the target complexes.Investigation of these magneticproperties of complexes showed the antiferromangetic coupling between the cyanide-bridged low-spin Fe(?)ion and Mn(?)ion.Additional,the weak magnetic interaction between the Mn(?)ions bridged by diamagnetic cyanide building blocks can be found in other complexes.2.A structurally characterized cis-dicyanidemetalate[Cr(2,2'-bipy)2(CN)2]Cl O4(1)building block and two mononuclear seven-coordinate macrocyclic manganese(?)complexes have been employed to assemble two cyanide-bridged heterometallic Cr?-Mn?complexes:{[Mn(L1)][Cr(2,2'-bipy)2(CN)2]2}{Cl O4}·4H2O(2)and{[Mn(L2)][Cr(2,2'-bipy)2(CN)2]2}{Cl O4}4·2H2O(3)(L1=2,13-dimethyl-3,6,9,12,18-pentaazabicyclo[12.3.1]octadeca-1(18),2,12,14,16-pentaen e,L2=2,13-dimethyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]octadeca-1(18),2,12,14,16-pen taene).Single-crystal X-ray diffraction analysis shows that 2 and 3 have similar cyanide-bridged cationic trinuclear Cr2Mn structures with free Cl O4-as balancing anions,in which the cyanide precursor acts as a monodentate ligand to connect the macrocyclic manganese(?)units.The coordination geometry of the manganese(?)centers in the two complexes is slightly distorted pentagonal-bipyramidal,with two cyanide nitrogen atoms at the trans-positions and N5 or N3O2 donor sets in thee quatorial plane provided by the macrocyclic ligand.Investigation of the magnetic properties reveals antiferromagnetic magnetic coupling between the cyanide-bridged Cr(?)and Mn(?)centers.By using trans-dicyanideiron(?)precursor as building block and chiral amine copper(?)compound as assemble segment,one chiral cyanide-bridged heterometallic Fe(?)-Cu(?)complexwiththeformula{[Cu(R/R-Chxn)2Fe(bpmb)(CN)2][Fe(bpmb)(CN)2]}·CH3OH·H2O(bpmb2-=1,2-bis(pyridine-2-carboxamido)-4-methylbenzenate,R,R-Chxn=R,R-1,2-diaminocyclohexane)has been prepared and characterized by elemental analysis,IR spectroscopy and X-ray structure determination.Single X-ray diffraction analysis reveals that this complex contains the cyanide-bridged cationic binuclear entity and the free anionic cyanide building block.The magnetic property study for this complex shows the weak ferromagnetic coupling between the neighboring Fe(?)and Cu(?)ions through the bridging cyanide group.3.Different transition metals compounds and tetradentate,pentadentate and octadentate cyanide precursors have been employed as building blocks to assemble cyanide-bridged hetetobimetallic complexes,resulting in three one-dimensional cyanide-bridged Fe?-Mg?,Ni?-Mn? and Pb?-Mn? complexes and one three-dimensional Cu?-Mg? complex and mononuclear manganese(?)compound and one manganese(?)ion pair.The structures of the complexes were characterized by IR and elemental analysis,and further confirmed by single crystal X-ray diffraction analysis.X-ray diffraction analysis shows that the one-dimensional Fe?-Mg? complexe is with novel paramagnetic;in the remaining four complexes,there is an antiferromagnetic magnetic coupling between two adjacent Mn(?)centers. |
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