The discontinuity of the X-ray Debye temperature of chromium near the Néel temperature

The integrated intensity of the lines 550 and 712 from a chromium powder sample was measured at 310.2 and 313.2°K, that is below and above the Néel temperature. From the difference in the integrated intensity of each line and after correction for thermal diffuse scattering, it was found that in this interval there exists a discontinuity in the Debye temperature of approx. 8°K. This discontinuity is 2.8 times larger than the one calculated from the discontinuity of the elastic constants data.