規則・不規則構造

ordered and disordered structure

[目次：結晶等(結晶構造／材料試料)]

たとえばCu₃Auの高温相ではCuとAuは区別なく不規則に面心立方構造の格子点を占める。低温相では原点をAuが占めるとするとCuは残りの3つの面心位置を規則正しく占める。このように外的条件（温度）が変わったときに構成原子が規則的に配列したり不規則的になる構造をいう。構造の規則・不規則化は合金ばかりでなく無機化合物でも起こる。規則化が起こると新しい回折斑点が回折図形に現れる。

For example, in the high-temperature phase of Cu₃Au, Cu and Au randomly occupy the lattice points of the face-centered structure. In the low-temperature phase, Au occupies the position of origin and Cu occupies the three face-centered positions. In this manner, the "ordered and disordered structure" means that when the external condition (temperature) changes, the structure of a substance changes where the constituent atoms are arranged orderly or randomly. The order-disorder transformation occurs in not only alloys but also inorganic compounds. If an ordered structure is formed, diffraction spots specific to the structure appear.

関連用語から探す