Abstract
The surface structure of a quasi-one-dimensional organic conductor Β-(BEDT-TTF crystal [BEDT-TTF is bis(ethylenedithio)-tetrathiafulvalene] was studied by scanning tunneling microscopy (STM). Twofold periodic modulation along the crystal a axis was observed on the crystal a-c plane with a top layer, similarly as the previous result obtained for the surface with a BEDT-TTF top layer. With the analysis using high-resolution STM images including the second BEDT-TTF molecular layer, the surface superstructure was found to be formed by alternate missing rows of molecules. To our knowledge, this is the first observation of an organic surface reconstruction involving such a drastic change in the molecular arrangement, which was comprehensively explained using a proposed model based on the charge balance in the surface layers.
DOI:https://doi.org/10.1103/PhysRevB.55.6773
©1997 American Physical Society