Infrared and Raman selection rules for elastic vibrations of spherical nanoparticles

M Kanehisa (1)

1 INSP - Institut des Nanosciences de Paris

It is shown that the assignment of parity in previous works neglected the vector nature of the elastic field and thus the resultant selection rules are erroneous. We propose a correct selection rule: Among the vibration modes of a sphere, only the torsional mode with angular momentum l=1 is observable by infrared absorption and the torsional mode with l=2 is observable by Raman scattering. The spheroidal modes cannot be observed by infrared or Raman spectroscopy in the dipole approximation.

Domaines: Matière Condensée [cond-mat]

M Kanehisa. Infrared and Raman selection rules for elastic vibrations of spherical nanoparticles. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2005, 72 (24), pp.241405. ⟨10.1103/PhysRevB.72.241405⟩. ⟨hal-01284402⟩