title: Molecular rectification of a helical peptide with a redox group in the metal-molecule-metal junction.
abstract: A helical hexadecapeptide immobilized on gold via a thiophenyl group at the N-terminal was analyzed by scanning tunneling microscopy under ultrahigh vacuum to obtain the I-V response at a molecular level. The attenuation factor of the electron transfer through the hexadecapeptide was determined by applying the Simons model to the I-V response to show better molecular conductance of the hexadecapeptide than dodecanethiol. Chemical modification at the C-terminal of the hexadecapeptide with a ferrocene unit, on the other hand, brought about significant changes in the I-V response, where the helical peptide became more conductive at the negative bias voltage. The molecular rectification behavior is due to the ferrocene unit regulating the direction of the electron transfer at the metal-molecule junction.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Kyoto 615-8510, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Kitagawa
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Morita
authors.forename: Shunsaku
authors.initials: S
authors.lastname: Kimura
mesh_terms: D000621:Aminoisobutyric Acids / Q000737:chemistry; D001565:Benzoates / Q000737:chemistry; D002942:Circular Dichroism; D004563:Electrochemistry; D005296:Ferrous Compounds / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D007930:Leucine / Q000737:chemistry; D000075163:Metallocenes; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012996:Solutions / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D000621:Aminoisobutyric Acids; D001565:Benzoates; D005296:Ferrous Compounds; D000075163:Metallocenes; D010455:Peptides; D012996:Solutions; C517217:ferrocene dicarboxylic acid; C100049:2-aminoisobutyric acid; D006046:Gold; D007930:Leucine