Fig. 5
From: Intrinsic anharmonic localization in thermoelectric PbSe
Thermal diffusivity anomaly absent a structural transition. a Thermal diffusivity measured using laser flash method on a piece of the same crystal used in the neutron scattering measurements. Lower panel shows a closeup view of a small negative kink in the data near 750 K (line is guide to the eye). b Single crystal diffraction pattern measured on the HYSPEC instrument above and below the temperature of the kink. The rings are aluminum powder rings from the crystal holder, which were used to calibrate the instrument when determining the PbSe lattice parameter. c Lattice parameter as a function of temperature determined by fitting the single crystal diffraction peaks. The refined lattice parameter of 6.124 ± 0.0005 Å at 300 K is in good agreement with the known value (the Al rings were used to calibrate the instrument assuming an Al lattice parameter of 4.046 Å at room temperature)
