Fabrication of molecular alignment at the specific sites on Cu(111) surfaces using self-assembly phenomena

We have successfully controlled the low-dimensional self-assembly formation of adenine molecules, one of the base molecules of DNA, between pre-adsorbed OMTP (2,3,7,8,12,13,17,18-octakis(methilthio) porphyrin) molecules which are immobile on Cu(lll) surfaces even at room temperature. The results of low temperature (approximately 70 K) scanning tunneling microscopy observation and molecular orbital calculation have revealed that OMTP molecules can connect with adenine molecules through hydrogen bonds to act as 'hub-molecules', i.e. as an anchoring site for their self-assembly. This study demonstrates a new concept and the first attempt to control the self-assembly formation at molecular level using these hub-molecules. (C) 2000 Elsevier Science B.V. All rights reserved.