title: Investigation of the scanning tunneling microscopy image, the stacking pattern, and the bias-voltage-dependent structural instability of 1,10'-phenanthroline molecules adsorbed on Au(111) in terms of electronic structure calculations.
abstract: A self-assembled monolayer of 1,10'-phenanthroline (phen) molecules on Au(111) was found to undergo a structural phase transition when the bias voltage is switched in scanning tunneling microscopy (STM) experiments (Phys. Rev. Lett. 1995, 75, 2376; Surf. Sci. 1997, 389, 19). The nature of two bright spots representing each phen molecule in the high-resolution STM images of phen molecules on Au(111) was identified by calculating the partial density plots for a monolayer of phen molecules adsorbed on Au(111) with tight-binding electronic structure calculations. The stacking pattern of chains of phen molecules on Au(111) was explained by studying the intermolecular interactions between phen molecules on the basis of first-principles electronic structure calculations for a phen dimer, (phen)(2). The structural instability of phen molecule arrangement caused by the bias-voltage switch was probed by estimating the adsorbate-surface interaction energy with the point-charge approximation for Au(111).
authors.affiliation: Department of Physical Sciences and Institute of Natural Basic Sciences, Wonkwang University, Iksan 570-749, South Korea.
authors.forename: Kee Hag
authors.initials: KH
authors.lastname: Lee
authors.forename: Youngsun
authors.initials: Y
authors.lastname: Suh
authors.forename: Changhoon
authors.initials: C
authors.lastname: Lee
authors.forename: Yong Gyoo
authors.initials: YG
authors.lastname: Hwang
authors.forename: H-J
authors.initials: HJ
authors.lastname: Koo
authors.forename: M-H
authors.initials: MH
authors.lastname: Whangbo