Abstract
AbstractRaman spectra of model improper ferroelastics (Hg_2Br_2 crystals) have been analyzed in a wide range of hydrostatic pressures. The baric dependences of the phonon frequencies are obtained. The revealing and anomalous behavior of the soft mode, which is genetically related to the acoustic phonon (ТА_1) at the Brillouin zone boundary (point X ) of the tetragonal phase, are most interesting. The buildup of the second acoustic phonon (ТА_2) from the same point has also been found in the ferroelastic-phase spectra, and its baric behavior has been investigated. The splitting of doubly degenerate phonons of the E _g symmetry has been revealed at fairly high pressures and explained.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
