| Abstract: | The NC stretching frequency in the potential‐dependent surface‐enhanced Raman scattering spectrum of 1,4‐phenylenediisocyanide (1,4‐PDI) is very sensitive to the electrode potential, and much the same peak shift is observed when an Au nanoparticle with mean diameter from 16 to 90 nm attached to 1,4‐PDI‐adsorbed gold nanogap system is exposed solely to organic vapors. This leads us to conclude that the surface potential of Au nanoparticles should change by as much as +0.57 and −0.34 V, respectively, in the presence of CCl4 and NH3 because of their respective electron‐withdrawing and electron‐donating properties, regardless of the size of Au nanoparticles in the gold nanogap system. Copyright © 2012 John Wiley & Sons, Ltd. |
