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Towards dielectric relaxation at a single molecule scale.

ABSTRACT: Dielectric relaxation lies at the heart of well-established techniques of dielectric spectroscopy essential to diverse fields of research and technology. We report an experimental route for increasing the sensitivity of dielectric spectroscopy ultimately towards the scale of a single molecule. We use the method of radio frequency scanning tunneling microscopy to excite a single molecule junction based on a polar substituted helicene molecule by an electric field oscillating at 2-5 GHz. We detect the dielectric relaxation of the single molecule junction indirectly via its effect of power dissipation, which causes lateral displacement. From our data we determine a corresponding relaxation time of about 300 ps-consistent with literature values of similar helicene derivatives obtained by conventional methods of dielectric spectroscopy.

SUBMITTER: Stetsovych V

PROVIDER: S-EPMC8861178 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Towards dielectric relaxation at a single molecule scale.

Stetsovych Vitalii V Feigl Simon S Vranik Radovan R Wit Bareld B Rauls Eva E Nejedlý Jindřich J Šámal Michal M Starý Ivo I Müllegger Stefan S

Scientific reports 20220221 1

Dielectric relaxation lies at the heart of well-established techniques of dielectric spectroscopy essential to diverse fields of research and technology. We report an experimental route for increasing the sensitivity of dielectric spectroscopy ultimately towards the scale of a single molecule. We use the method of radio frequency scanning tunneling microscopy to excite a single molecule junction based on a polar substituted helicene molecule by an electric field oscillating at 2-5 GHz. We detect ...[more]

PMID: 35190585

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