Using Neutron Scattering to Study Hydrocarbons and other Materials

摘要

Neutron scattering has been widely used in materials research during the last decade, thanks to advances in neutron scattering technqiues and facilities. It not only complements other scattering technqieus such as x-ray scattering or light scattering, it in many cases has its unparalleled advantages, because of unique features of neutore and its interaction with matters. The mostly used neutron scattering method is small angle neutron scattering, or SANS. SANS is a type of static elastic scattering. Because it does not exchange energy with the probe dsample, the scattering does not carry inforamtion of the dynamics. Neutron scatters a small angle due to the density fluctuatiosn in the samkple, so the scattering intensity as a function of the angle carries inforamtion of the sample's microstructure. Indeed, the scattering intensity I(q) as a function of the scattering wavevector, q, is a Fourier transform of the rela space density function. Here q combines both the scattering angle #theat# and neutron wavelength #lambda#,q = 4#pi#(sin (#theta#/2))/#lambda#