Short Range Order in Interstitial Alloys.

1)通过弹性中子扩散散射测量，确定了TiO_(3.32)&gT；单晶中氧排列的短程有序参数。通过实验强度与理论强度的最小二乘拟合，从总的漫射强度中分离出短程有序项。氧原子的第一、第三和第五邻原子排列更倾向于被空位包围，而不是被氧原子包围。而氧原子优先占据第二和第四近邻位置。2)通过弹性中子扩散散射测量，确定了单晶中氦排列的短程有序参数。在钒晶格的四面体间隙位置的第一、第二和第三邻位处，空位-氚原子对具有择优构型，而在第四邻位处，则出现了氘-氚原子对的择优构型。3)用中子小角散射研究了Nb-N和Ta-N合金中氮原子的局域原子排列。低Q区的扩散强度揭示了氮原子碎屑的存在。

1) Short-range order parameters for oxygen arrangement in single crystal of Tio_<3.32> were determined by measurements of elastic neutron diffuse scattering. The short range order term were separated from the total diffuse intensity by least squares fit of the experimental intensity with a theoretical one. The first-, third and fifth-neighbor atomic arrangement of the oxygen atom has a preference to be surrounded by vacancies rather than by oxygen atoms. While, the second- and fourth-neighbor site are occupied preferentially by oxygen atoms.2) Short-range order parameters for deuterium arrangement in single crystal of VD_<0.81> were determined by measurements of elastic neutron diffuse scattering. The preferential configrations of vacancy-deuterium atom pair are found at first-, second-, and thirdneighbors of tetrahedral interstitial sites of the host vanadium lattice whereas the deuterium-deuterium atom pairs occur at the fourth neighbors. These features are similar to those in the ordered structure below T_c.3) Local atomic arrangements of nitrogen atoms in Nb-N and Ta-N alloys have been studied by neutron small angle scattering. The diffuse intensity of low Q region revealed the existence of the nitorogen atom clasters.