Scanning tunnelling spectroscopy and manipulation of double-decker phthalocyanine molecules on a semiconductor surface. (7th August 2017)

• Record Type: Journal Article
• Authors: Pan, Yi; Kanisawa, Kiyoshi; Ishikawa, Naoto; Fölsch, Stefan
• Is Part Of: Journal of physics. Volume 29:Number 36(2017)
• Publication Date: 2017-08-07
• Subjects: scanning tunneling microscopy -- semiconductor surfaces -- III–V semiconductors -- STM manipulations of single atoms and molecules; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa7dc4
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: A scanning tunnelling microscope (STM) operated at 5 K was used to study dysprosium biphthalocyanine (DyPc2 ) molecules adsorbed on the inert III–V semiconductor surface InAs(1 1 1)A. Orbital imaging and scanning tunnelling spectroscopy measurements reveal that the molecular electronic structure remains largely unperturbed, indicating a weak molecule-surface binding. The molecule adsorbs at the In vacancy site of the (2 × 2)-reconstructed surface and is highly sensitive to current-induced excitations leading to random rotational fluctuations. Owing to the weak surface binding, individual molecules can be precisely repositioned and arranged by the STM tip via attractive tip-molecule interaction. In this way, DyPc2 dimers of well-defined internal structure can be assembled which exist in two conformations of equivalent appearance. A binary switching between these two conformers can be induced by injecting electrons into one of the two molecules. The conformational change of the dimer proceeds via a concerted molecular rotation and minor lateral displacement. The synchronised switching observed here is attributed to steric interactions between the two molecules constituting the dimer.