Research Of The Structure-Property Regulation And Its Assembly Chemistry For Clusters/Polymers Constructed By Bis-triazole Ligand

The study of SMMs have attracted widely interest because of their tremendous potential applications in high-density information,quantum computing,and molecular spintronics.So far,thousands of SMMs with various structures have been reported.However,controllable synthesis of excellent SMMs with excellent properties is still a challenge.To modify and regulate the existing SMMs and to study its assembly process has become imperative.Its significance is not only to get better SMMs,but also to enlighten us how to get better SMMs.In this article,we not only modify series of clusters based on 2,2'-H2dpbt/4,4'-H2dpbt ligand such as a Co14 supramolecular cluster through adjusting the solvent,pH,temperature,and replace the ancillary ligand,but also study the assembly process of them.This thesis includes six chapters.Chapter 1 gives a simple overview of the development of single molecule magnet.And introduces the modification of single molecular magnets reported before in regulating the ligand substitution,symmetry and the growth and extension of the cluster based unit.Especially for the last aspect,we expound in three directions as follow:firstly,complexes based on SMMs-based subunit connected by long bridging ligand;secondly,complexes based on SMMs-based subunit connected by short bridging ligand;finally,the fused systems based on SMMs-based subunit.Besides,we systematically summarized the works of the domestic and foreign well-known scientists in this field.Chapter 2 describes six Co14 supramolecular clusters with various symmetries;[Co14(?3-OH)4(2,2'-dpbt)6Cl12·14 CH2CH3OH(1);[Co14(?3-OH)4(2,2'-dpbt)6Cl12]·11 CH3CN(2);[Co14(?/3-OH)4(2,2'-dpbt)6Cl12·]3 CH3CH2COCH3(3);[Co14(?3-OH)4(2,2,-dpbt)6Cl12]·23 C6H10O(4);[Co14(?3-OH)4(2,2'-dpbt)6Cl12]· Et3NH·Cl·2 CH3CHOHCH3(5);[Co14(?3-OH)4(2,2'-dpbt)6Cl12]· 3.5 CH3COCH3(6).Different solvent molecules provide different environment of the hydrogen bond.Different environment of the hydrogen bond could lead to the different way of stacking and tortuosity for the Co 14 supramolecular clusters,which further lead to the transformation of the magnetic behavior.Besides,experimental results show that inert solvent could replace the environment of the hydrogen bond of the Co14 supramolecular clusters mildly.This process contributes to the single-crystal to single-crystal transformation.And the active solvent could lead to the dissociation of the Co 14 supramolecular clusters.In chapter 3,we achieved an intuitional pH driven hierarchical assembly from a Co14 supramolecular cluster[Col4(CH3O)4(2,2'-dpbt)6Cl12]·14CH3OH(8)to a 2D MOF based on the Co14 cluster subunit {[Co14(CH3O)10(2,2'-dpbt)6C16]·12CH3OH}n(9).We have traced the assembly process through XRPD and SEM.The 2D MOF reveals the coexistence of spin canting and long-range magnetic ordering and higher TB than the Co14 supramolecular cluster.Besides,the 2D MOF also reveals excellent CO2 adsorption performance.In chapter 4,we introduce a shorter ancillary ligand H2ptd to replace 2,2'-H2dpbt.As a result,a Co13 supramolecular cluster[Co13(?3-OH)3(?3-Cl)(dpbt)5(ptd)Cl10][Co(H2O)2Cl2]·CH3CHOHCH3(10)which revealed higher TB than the Co14 supramolecular clusters is obtained.Besides,we also obtain it's dimer:a Co24 supramolecular cluster[Co24(?3-OH)6(?3-Cl)2(dpbt)10(ptd)2Cl16]·2CH3CH2OH(11),which inherits the spin canting andslow relaxationbehavior from the Co13 supramolecular cluster.It is worth mentioning that the Co24 supramolecular cluster revealed higher TB than the Co13 supramolecular cluster.And it is the largest Co(?)-based SMMs up to now.Moreover,the temperature driven hierarchical assembly from the Co13 supramolecular cluster to the Co24 supramolecular cluster is achieved.In chapter 5,we constructed a 1D coordination polymer[Co2(?2-O)2Cl2(2,2'-H2dpbt)(H2O)2]n(12)based on a Co2 subunit with mirror inversion symmetry,and a 2D coordination polymer {[Co5(4,4'-dbpt)2Cl8].2(C2H5)3NH}n(13)based on a Co5 subunit.Both of them revealed the spin canting andslow relaxationbehavior.It is worth mentioning that the former reveals SMM behavior with the energy barrier of 91.71(6)K,which is the highest one in the Co-based SMMs reported before.In chapter 6,we constructed four interesting Cdn(n=4,6,7)based coordination polymers {[Cd7(?3-O)6(4,4'-dbpt)3]·6CH3OH}n(14);{[Cd3Cl3(2,2'-dbpt)3]·2H2O}n(15);{[Cd3I3(2,2'-dbpt)3]·H2O}n(16);{[Cd2Br2(2,2'-dbpt)]·H2O}n(17)by regulating the different anion such as O2-,Cl-,Br-,I-.Due to the difference of the anionic radius,their clusters based subunit and the overall frameworks have been changed subtlety,and their corresponding fluorescence properties are also changed interestingly.