Fabiani E, Fontana A, Buchenau U
CEA LETI Minatec Departement des Technologies pour la Biologie et la Sante, 38054 Grenoble Cedex 9, France.
J Chem Phys. 2008 Jun 28;128(24):244507. doi: 10.1063/1.2937731.
The incoherent approximation for the determination of the vibrational density of states of glasses from inelastic neutron or x-ray scattering data is extended to treat the coherent scattering. The method is applied to new room temperature measurements of vitreous silica and germania on the thermal time-of-flight spectrometer IN4 at the High Flux Reactor in Grenoble. The inelastic dynamic structure factor at the boson peak turns out to agree reasonably well with simulation results, but the long-wavelength fraction exceeds the expectation of the Debye model, in particular, in germania.
用于根据非弹性中子或X射线散射数据确定玻璃态振动态密度的非相干近似被扩展到处理相干散射。该方法应用于在格勒诺布尔高通量反应堆的热飞行时间光谱仪IN4上对石英玻璃和锗玻璃进行的新的室温测量。结果表明，玻色子峰处的非弹性动态结构因子与模拟结果相当吻合，但长波部分超过了德拜模型的预期，尤其是在锗玻璃中。
