A Morse manipulator like molecule able to modulate the electronic standing wave pattern of metallic Shockley surface states is presented. Its design is based on a molecular arm holding a phenyl whose distance to the metal surface is controlled by the tip apex of an STM. The standing wave patterns are calculated using an extension of the N-ESQC technique. The corrugation of the surface state modulation is proposed to be detected by a small 127 k Omega atomic scale tunnel junction supposed positioned very close to the surface and a few nanometers away from the molecule. A variation of 150 Omega of this junction resistance is detected for a phenyl surface distance variation from 0.4 to 0.24 nm. (c) 2006 Elsevier B.V. All rights reserved.