The Investigation Of Hybrid Spin-Crossover Seminconducting Materials Based On TCNQ

Switchable molecule-based material have attract much attention since it might provide answers about the conventional magnetic storage devices approaching the technological and physical limits,with the potential application of molecular switches,single molecular magnets or molecular logic gates.Spin-crossover(SCO)complex,a typical kind of switchable materials,have different magnetic and physical properties depended on which electronic state it is in,high-spin(HS)or low-spin(LS)state,and the conversion can be induced by applying external stimuli,such as pressure,temperature,light,magnetic field or inclusion guest molecules.To prepare promosing multifunctional Spin-crossover materials,scientist have made much endeavor to the synergy of Spin-crossover behavior and other properties,such as magnetic order,liquid crystal,host-guset chemistry,fluorescence and electric properties.Considering the significant applicability of these materials,electrical properties of SCO compounds have been study over the last decade,since the current signal induced by electronic state change is easier to be measured and fitter for practical application than magnetic susceptibility and optical signal.To this end,we select different SCO cations and TCNQ conductive unit to construct new SCO semiconducing materials to investigate their properties under different external conditions.In this thesis,two parts are investigated:(1)Monocular Co(II)SCO semiconducting complex.One Co?-TCNQ SCO Semiconducting compound have been synthesized,which exhibit semiconducting and incomplete SCO behavior and electron localization on TCNQ units.(2)Monocular Fe(II)SCO semiconducting complex.Two Fe?-TCNQ SCO Semiconducting compound have been synthesized,whose activation energy variance in the SCO temperature region,suggesting the evolution of activation energy upon temperature increasing might be caused by a significant slippage between the adjacent trimers,[TCNQ]32-.