Negative thermal expansion ofReO3: Neutron diffraction experiments and dynamical lattice calculations

Tapan Chatterji, Paul F. Henry, R. Mittal, S. L. Chaplot
2008 Physical Review B  
We have investigated the temperature variation of the unit-cell volume of ReO 3 by neutron diffraction. The lattice parameter and the unit-cell volume decrease continuously as the temperature is increased from T = 2 K to about T = 200 K. After exhibiting minima at about 200 K they increase with increasing temperature linearly up to about 305 K, the maximum temperature investigated during the present experiment. We attribute the negative thermal expansion of ReO 3 to be the results of rigid
more » ... sults of rigid antiphase rotations of the neighboring ReO 6 octahedra. We have done model lattice dynamical calculation of phonon dispersions, thermal expansion, and atomic displacement parameters in ReO 3 . The results of these calculations are in agreement with the experimental results.
doi:10.1103/physrevb.78.134105 fatcat:gmwfkzccjvfbhbsmjpseoqxhri