Design and Syntheses of Paramagnetic Dinuclear Metal Complexes Inducing Significant Cooperative Effects and Their Multinuclear NMR Study

1. 新双核配合物的制备：(1)合成了以草酸、氟、4,5 -咪唑二羧基、3.5吡嗪二羧基、吡唑（羟基）为桥接配体的[Cr_2 (X)_2 (acac)_2]型（acac=乙酰丙酮）新型双核配合物。(2)系统合成双核配合物((N-N) _2 Cr(OH)(RCOO)Cr(nta)]^+((N-N)=(NH_3)_2，乙二胺，R， R-环己二胺；nta = nitrilotriacetato;R=CH_<>Cl， H, C_6H_5, CH_3)建立。(3)制备了新的二羟基双核配合物[Cr_2(OH)_2((R， R)-chxn)_4]^<4+>和氢氧水双核配合物[Cr_2(OH)_2(H_2O)_2 ((R， R)-chxn)_4]^<4+>, [Cr_2(OH)(H_2O) (edtrp)_2]和[Cr_2(OH)(H_2O) (S)-pdtrp)_2]并对其进行了表征。2 . x射线结构分析：对两种同构晶体[(tn)_2Cr(OH)_2M(nta)]Cl-1.5H_2O（M=Cr, Co）进行了x射线结构分析，并对其分子结构进行了比较，比较了中心金属离子之间键长和键角的差异。核磁共振光谱:[(n n) _2Cr (OH) _2M (nta)) ^ + (M =铬(III),有限公司(III));（N-N）=(NH_3)_2，乙二胺，R，环己二胺，2,2 '-联吡啶；考虑到顺磁性CR （III）离子对[CR - CR]和[CR - col]配合物的影响，对nta=nitrilotriacetato)、^1H-、^2H-NMR谱进行了观察和检验。测量了[(N-N)_2Cr(OH) (CD_3COO)Cr (nta)]^+中桥接配体的^2HNMR谱。磁化率测量：完成了自动测量磁化率的法拉第仪的构造。测量了在本研究项目期间获得的新的双核CR （III）配合物的温度依赖磁化率，并讨论了它们的磁相互作用与桥接配体的电子性质的关系。

1. Preparation of new dinuclear complexes :(1) New dinuclear complexes of[Cr_2 (X)_2 (acac)_2] type (acac=acetylacetonato) with bridging ligands such as oxalato, fluoro, 4, 5-imidazoledicarboxylato, 3.5pyrazinedicarboxylato, pyrazole (hydroxo) were synthesized.(2) A systematic synthetic route to dinuclear complexes ( (N-N)_2 Cr(OH)(RCOO)Cr(nta)]^+((N-N)=(NH_3)_2, ethylenediamine, R, R-cyclohexanediamine ; nta=nitrilotriacetato ; R=CH_<>Cl, H, C_6H_5, CH_3) was established.(3) New dihydroxo dinuclear complex[Cr_2(OH)_2 ( (R, R)-chxn)_4]^<4+> and hydroxoaqua dinuclear complexes[Cr_2(OH)_2(H_2O)_2 ( (R, R)-chxn)_4]^<4+>, [Cr_2(OH)(H_2O) (edtrp)_2] and[Cr_2(OH)(H_2O) ( (S)-pdtrp)_2] were prepared and characterized.2. X-ray structural analyses :The X-ray structural analyses were performed for two isomorphous crystals[(tn)_2Cr(OH)_2M(nta)]Cl-1.5H_2O(M=Cr, Co), and their molecular structures were compared with each other with respect to the difference in bond lengths and bond angles between central metal ions.3. NMR spectra :For[(N-N)_2Cr(OH)_2M(nta)]^+ (M=Cr(III), Co(III)) ; ((N-N)=(NH_3)_2, ethylenediamine, R, Rcyclohexanediamine, 2, 2'-bipyridine ; nta=nitrilotriacetato), ^1H-, ^2H-NMR spectra were observed and examined in view of the influence from the paramagnetic CR (III)ion in[Cr-Cr)and[Cr-Col complexes. ^2HNMR spectra of the bridging ligands in[(N-N)_2Cr(OH) (CD_3COO)Cr (nta)]^+ were measured.4. Magnetic susceptibility measurements :The construction of a Faraday apparatus for automatic magnetic susceptibility measurement was completed. The temperature dependent magnetic susceptibility for new dinuclear CR (III) complexes obtained throughout the present research project term was measured and their magnetic interactions were discussed in relation with the electronic properties of the bridging ligands.