The solid solution Sr1-xCaxMoO3 (x = 0, 0.05, 0.1, 0.13, 0.15 & 0.17) has successfully been synthesised and X-ray Powder diffraction has revealed the occurrence of structural phase transitions, from cubic Pm-3m to tetragonal I4/mcm, and then to orthorhombic Imma as the value of x increased. Discontinuities were observed in the cell parameters and bond lengths and angles at the transition from tetragonal to orthorhombic symmetry as a result of the switching of the octahedral rotation axis at the tetragonal to orthorhombic transition. The increased octahedral tilting could also be linked to the decrease in the band gap from 2.20 eV to 2.10 eV as x increased from 0 – 0.17.
Bibliographical noteWe acknowledge the University of Aberdeen for provision of a studentship for Harriet Hopper.
- octahedral tilting
- phase transition
- optical properties