In order to investigate the electrical properties of electron transport through the single molecule,a chip for the mechanically controllable break junction(MCBJ) was fabricated.With such a chip and corresponding mechanical setup,a pair of nanoelectrodes can be obtained and the distance between the electrodes can be adjusted with picometer accuracy.The molecular junctions bridged by metal ion(electrode-molecule-metal ion-molecule-electrode junctions) were established using the technology of mechanically cont...