The optically induced oscillatory response of a spherical two-component, shell-core structured, nanoparticle by nodeless elastic vibrations of soft peripheral shell against hard and dynamically immobile inner core is considered. The eigenfrequencies of the even-parity, spheroidal, and odd-parity torsional vibrational modes trapped in the finite-depth shell are obtained, which are of practical interest for modal specification of individual resonances in spectra of resonant scattering of long wavelength ultrafine particles.
