非晶态合金Cr-B体系局域结构及催化性质的研究

The study on local structure and catalytic property of Cr-B amorphous alloy

利用密度泛函理论方法(DFT),对代表性团簇Cr_3B_2的所有可能构型进行优化计算,在分析优化构型的基础上,对非晶态合金Cr-B体系的局域结构、成键及催化性质进行研究,结果表明:在非晶态合金Cr-B体系中存在B-B间近距离接触;团簇Cr_3B_2优化构型主要以三重态存在,且三重态构型所占比例总和高达97.72%,其中四角锥构型1^((3))所占比例为25.40%,在所有优化构型中所占比例最高;在三重态团簇Cr_3B_2中,构型的变化对Cr-Cr键和Cr-B键的成键强度起到此消彼长的作用;Cr-B非晶态合金对C_2H_4具有潜在的催化活性。

After optimizing and calculating all possible configurations of the representative cluster Cr3B2by using the Density Functional Theory（DFT） method, this paper makes research on the local structure, bonding and catalytic property of amorphous alloy Cr-B system on the basis of analyzing the optimized configurations, conclusions are drawn as follows： B-B close contact can be found in amorphous alloy Cr-B system; the optimized configurations of cluster Cr3B2 mainly exist in triplet state, and the gross proportion in triplet state is 97.72%, the quadrangular pyramid configuration 1（3） takes up the largest proportion of 25.40%. For cluster Cr3B2 in triplet state, the change of configuration takes opposite effect on the bonding strength of Cr-Cr and Cr-B; Cr-B amorphous alloy has potential catalytic activity to C2H4.