To better understand the role of crystal structures and local disorder in the photonic properties of the system (1 - x)CaWO4 - xCdWO4 with 0 < x < 1, two specific phases with compositions x = 0.5 (scheelite phase) and 0.8 (wolframite phase) have been studied by scanning and transmission electron microscopies. High-resolution electron microscopy images and image simulations, associated with X-ray diffraction data, allowed confirming the lattices and space groups I41 /a and P2/c of the two scheelite and wolframite phases, at the local scale. The electron microscopy data show the existence of a high degree of crystallization associated with statistical distribution of Ca or Cd atoms on a Ca1- x Cdx site in each lattice.
Keywords: Calcium cadmium tungstates; electron microscopy; high-resolution electron microscopy; simulated images; solid solutions.
© 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.