The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes（CTCs） including PrQ（TCNQ） 2,MPM（TCNQ） 2,and MEM（TCNQ） 2,have been investigated by scanning tunneling microscop...The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes（CTCs） including PrQ（TCNQ） 2,MPM（TCNQ） 2,and MEM（TCNQ） 2,have been investigated by scanning tunneling microscopy（STM）.The three bulk-truncated surfaces are all ac-surface,which are terminated with TCNQ molecular arrays.On the ac-surface of PrQ（TCNQ） 2,the TCNQ molecules form a tetramer structure with a wavelike row behavior and a 纬 angle of about 18掳 between adjacent molecules.Moreover,the dimer structures are resolved on both ac-surfaces of MPM（TCNQ） 2 and MEM（TCNQ） 2.In addition,the tetramer structure is the most stable structure,while the dimer structures are unstable and easily subject to the STM tip disturbance,which results in changeable unit cells.The main reasons for the surface stabilization variation among the three ac-surfaces are provided by using the ＇蟺-atom model＇.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10804010,50772015,60977015,and 10974019)the National Basic Research Program of China(Grant No.2006CB932301)the Scientific Research Foundation for the Returned Overseas Chinese Scholars of Ministry of Education
文摘The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes（CTCs） including PrQ（TCNQ） 2,MPM（TCNQ） 2,and MEM（TCNQ） 2,have been investigated by scanning tunneling microscopy（STM）.The three bulk-truncated surfaces are all ac-surface,which are terminated with TCNQ molecular arrays.On the ac-surface of PrQ（TCNQ） 2,the TCNQ molecules form a tetramer structure with a wavelike row behavior and a 纬 angle of about 18掳 between adjacent molecules.Moreover,the dimer structures are resolved on both ac-surfaces of MPM（TCNQ） 2 and MEM（TCNQ） 2.In addition,the tetramer structure is the most stable structure,while the dimer structures are unstable and easily subject to the STM tip disturbance,which results in changeable unit cells.The main reasons for the surface stabilization variation among the three ac-surfaces are provided by using the ＇蟺-atom model＇.
