Kirstein O, Prager M, Grimm H, Buchsteiner A, Wischnewski A
Bragg Institute, Australian Nuclear Science and Technology Organisation, Menai, New South Wales 2234, Australia.
J Chem Phys. 2007 Sep 7;127(9):094504. doi: 10.1063/1.2760205.
Quasielastic neutron scattering experiments were carried out using the multichopper time-of-flight spectrometer V3 at the Hahn-Meitner Institut, Germany and the backscattering spectrometer at Forschungszentrum Julich, Germany. Activation energies for CH(3)X, X=F, Cl, Br, and I, were obtained. In combination with results from previous inelastic neutron scattering experiments the data were taken to describe the dynamics of the halides in terms of two different models, the single particle model and the coupling model. Coupled motions of methyl groups seem to explain the dynamics of the methyl fluoride and chloride; however, the coupling vanishes with the increase of the mass of the halide atom in CH(3)Br and CH(3)I.
使用德国哈恩-迈特纳研究所的多斩波器飞行时间光谱仪V3和德国于利希研究中心的背散射光谱仪进行了准弹性中子散射实验。获得了CH(3)X(X = F、Cl、Br和I)的活化能。结合先前非弹性中子散射实验的结果,采用单粒子模型和耦合模型这两种不同模型来描述卤化物的动力学。甲基的耦合运动似乎可以解释氟甲烷和氯甲烷的动力学;然而,在CH(3)Br和CH(3)I中,随着卤原子质量的增加,这种耦合消失了。