We report the first evidence of Raman scattering from surface phonons of a pristine metal surface . Our study reveals a Raman-active surface vibrational resonance on Cu(110) with a surprisingly large scattering
efficiency. With the incident photon energy close to the energy of the Cu(110) surface state electronic transition , the Raman scattering from the surface optical resonance can be significantly enhanced, while
any contribution from bulk phonons is absent. Density functional theory-based calculations of the electronic band structure show that the observed Raman signal can be unambiguously attributed to the coupling of
this specific mode with electronic surface states, and provide insight into the mechanism causing the strong enhancement of the Raman Scattering.