Quantum Chemical Study on the Interstitial Impurities in Metals and Alloys

使用DV-Xa方法对含有间隙杂质的金属和合金的模型团簇进行了第一性原理分子轨道计算，即氢、氦、碳、氮和氧。在铁中，当H-Fe的键长在o位点增加20%，在t位点增加10%时，整个簇上的重叠居群总和达到最大值。分别;它们暗示了晶格扭曲的数量。溶质原子对间隙杂质稳定性的影响以类似的方式进行了研究。与这些研究并行。1)对某些金属和金属间化合物的正电子寿命进行了研究，2)对电子能量损失的近边结构进行了理论计算。

First priciples molecular orbital calculations using DV-Xa method have been performed on model clusters of metals and alloys containing interstitial impurities, i.e., hydrogen, helium, carbon, nitrogen and oxygen. In iron, the sum of overlap populations over the whole cluster showed maximum values when the bond-length of H-Fe and was increased by 20% at O-site, and 10% at Tsite.respectively ; They imply these amounts of lattice distortion.Effects of solute atoms for the stability of the interstitial impurities were pursued in a similar manner.In parallel to these studies. 1) positron lifetime study of some metals and intermetallic compounds and 2) theoretical calculations of electron energy-loss near edge structures have been made.