Direct identification of conformational isomers of adsorbed oligothiophene on Cu100
Takashi Yokoyama1, Saki Kurata, Shoji Tanaka
1Graduate School of Integrated Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan. tyoko@yokohama-cu.ac.jp
Abstract:
A direct conformational analysis using scanning tunneling microscopy (STM) has been performed for individual adsorbed alpha-octithiophene molecules on Cu(100). s-cis and s-trans conformational isomers are induced by the rotational flexibility of individual thiophene rings. By adding bulky N-silyl substituents to octithiophene, we successfully identify the s-cis and s-trans conformational isomers using STM. The obtained relative abundances of the s-cis and s-trans conformations are analyzed using ab initio molecular orbital calculations.
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