| As the important bridge that connects molecular devices to external,molecular wire plays a function of connection and information transmission,and has become the current research hotspot.Made up of transition metal complexes as the electroactive center and conjugated organic ligand bridge,metal organic molecular wire is seen as the molecular wire with potential application prospect.Electronic transmission performance of this kind of molecular line mainly depends on medium,molecular configuration,metal core and bridging ligand.Systematic research on the influence factors of electronic transmission performance in metal organic molecular wire can provide support for design of molecular wire with excellent performance.With 1.4-divinyl phenyl as the bridging ligand,the author systematically inspects the influence on the electronic transmission performance of ruthenium metal complexes molecular wire which electrical property,number and replacement position of bridging ligand substituent have.The detailed research content is as follows:With 1.4-divinyl phenyl as the bridging ligand,we synthesis a series of double ruthenium[RuCl(CO)(PMe3)3]2(μ-CH=CH-Ar-CH=CH)compounds which contain one,two(ortho-position or para-position)and four substituents.Meanwhile,through use of voltammetry technology,infrared technology and UV-VIS-NIR in-situ electrochemical spectroscopy technique,we try to inspect the influence on the electronic transmission performance of these bimetallic complexes which electrical property,number and replacement position of bridging ligand substituent have.Electrochemical study shows:(1)This kind of bimetallic complexes have continuous two-step single electron oxidation reduction process.(2)When there is single electron-donating substituent or electron-withdrawing substituent on 1.4-divinyl phenyl,the change of electron cloud density on the bridging ligand has promotion or weakness for the electrocmmunication of dinuclear ruthenium compounds.(3)When there are two substituents in para-position on the bridging ligand of 1.4-divinyl phenyl,electron donating substituent benefits the mutual interaction between metals;when the two substituents are in ortho-position,stereo-hindrance effect are shown,and the transmission electronic performance becomes weak when it is compared to ortho-position.(4)When four electron-donating groups are brought in 1.4-divinyl phenyl,the electron-donating ability obviously declines,which shows a certain withdrawing electron performance.(5)When one,two and four electron-withdrawing substituents are brought in 1.4-divinyl phenyl,the electron cloud density on the bridging ligand is decreasing gradually,and the mutual interaction between the metals becomes weak.The above research shows that the mutual interaction between two metal rutheniums can be adjusted and controlled through modification on 1.4-divinyl phenyl.The electrical property,number and replacement position of the substituent have influence on the charge transfer among mental centers. |
