Disentangling electron- and electric-field-induced ring-closing reactions in a diarylethene derivative on Ag(1 1 1). (13th June 2017)

• Record Type: Journal Article
• Authors: Reecht, Gaël; Lotze, Christian; Sysoiev, Dmytro; Huhn, Thomas; Franke, Katharina J
• Is Part Of: Journal of physics. Volume 29:Number 29(2017)
• Publication Date: 2017-06-13
• Subjects: molecular switch -- scanning tunneling microscopy -- molecular electronic; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa75c1
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Using scanning tunneling microscopy and spectroscopy we investigate the adsorption properties and ring-closing reaction of a diarylethene derivative (C5F-4Py) on a Ag(1 1 1) surface. We identify an electron-induced reaction mechanism, with a quantum yield varying from 10 −14 –10 −9 per electron upon variation of the bias voltage from 1–2 V. We ascribe the drastic increase in switching efficiency to a resonant enhancement upon tunneling through molecular orbitals. Additionally, we resolve the ring-closing reaction even in the absence of a current passing through the molecule. In this case the electric-field can modify the reaction barrier, leading to a finite switching probability at 4.8 K. A detailed analysis of the switching events shows that a simple plate-capacitor model for the tip-surface junction is insufficient to explain the distance dependence of the switching voltage. Instead, describing the tip as a sphere is in agreement with the findings. We resolve small differences in the adsorption configuration of the closed isomer, when comparing the electron- and field-induced switching product.