Effects of pressure and temperature on the vibronic as well as the thermodynamic properties of LiYF4and LiYbF4

Since the tetragonal lithium rare earth fluoroscheelites are excellent laser media with a wide bandgap, studies of their vibronic and thermodynamic properties would help render valuable insights in contriving better technology towards achieving higher lasing efficiency. Hence, in this paper, we try to enunciate a brief account on lattice dynamical calculations of the pressure as well as the temperature dependence of various underlying physical phenomena of two such para-elastic scheelites, namely, LiYF4 and LiYbF4. Our computations based on a rigid ion model yield a good deal of parity with the measured Raman data of LiYF4. These are then comfortably extended for LiYbF4, to give way to a useful comparative analysis for further studies.