Evidence for a Partial F.C.C.—H.C.P. Phase Transition in Solid Neon from Raman Scattering

Abstract

Abstract Raman spectra from crystalline neon are investigated that show a sharp peak at 25.2 cm −1 identified as first order. Its energy is very close to that of the TA phonon at the L‐point of the f.c.c. Brillouin zone. A first‐order Raman effect is expected for the h.c.p. structure with the Raman‐active TO phonon almost degenerate with the TA phonon at the L‐point. From the haracteristic temperature dependence of the intensity of the peak, from its sharpness, and from its energetic position a partial phase transition at 10.5 K is deduced.