| Summary: | 碩士 === 國立臺灣大學 === 化學研究所 === 100 === The goal of this thesis is to synthesize heteronuclear metal string including nickel and molybdenum with 2-α-pyridylamino-1,8-naphthyridine (Hpyany) . The Mo -Mo bond distance of [Mo2(Hpyany)2(pyany)2](PF6)2 is about 2.09 A which corresponds to a metal - metal quadruple bond. There are two ligands without deprotonation. The tetranuclear linear metal chain, [Mo2Ni2(pyany)4(Cl)2](ClO4), is helically wrapped by four all syn form type ligands. The metals of nickel and molybdenum arrange in order of Mo1-Mo2-Ni1-Ni2 with Cl- axial ligands both at two side of metal string.
In the CV analysis, the [Mo2Ni2(pyany)4(Cl)2](ClO4) have two regions of oxidative potentials and each region has three pairs of redox couples. The E1/2 of potentials at lower oxidative region is 0.130V、0.248V and 0.386V; the E1/2 of potentials at higher oxidative region is 0.834V、0.934V and 1.024V, respectively, with OTTLE and UV/vis spectrum, the lower region is assigned as oxidation on Ni23+ to Ni24+，and the higher region is assigned as oxidation on Mo24+, respectively.
The magnetic susceptibility shows that [Mo2Ni2(pyany)4(Cl)2](ClO4) is paramagnetic. The μeff values of Mo2Ni2(pyany)4(Cl)2](ClO4) is 4.08 B.M. which is smiliar to the μspin-only value 3.87 B.M. in 300K. The electronic configuration (S = 0) of Mo24+ bimetal clusters is the diamagnetic quadruple bond, and the Ni23+ ion is consistent with the mixed valence unit comparison to the electronic configuration (S = 3/2).
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