Co-P非晶态合金电子性质和局域结构的理论研究

根据Co P非晶态合金结构的短程有序和结构中可能存在P -P相互作用的实验事实 ,选择了单磷原子簇模型ConP(n =1～ 5 )和双磷原子簇模型ConP2 (n =1～ 4 ) ,用密度泛函理论方法对其进行计算 .结果表明 ,在单磷Co2 P( 2 ) 、Co3 P( 1) 及Co4P( 2 ) 模型体系中 ,Co原子供给P原子电子 ,与电负性规则一致 ,同时Co和P之间具较强化学作用 ,可以形成稳定的原子簇 ;而在双磷和单磷原子簇Co5P( 1) 模型体系中 ,形成的原子簇不稳定 ,采用单磷Co2 P( 2 ) 、Co3 P( 1) 及Co4P( 2 ) 模型能较好地反映Co P非晶态合金的结构特点 .

Theoretical Study on Electron Property and Local Structure in Co-P Amorphous Alloy

In order to study the electron property and the microlocal structure of Co-P amorphous alloy, a series of single-P (Co_nP) and two-P (Co_nP_2)cluster models were chosen according to the experiment fact of the possible presence of direct P-P contact and short-range-ordering in the amorphous alloy. Co_nP and Co_nP_2 cluster models were calculated with the DFT method and calculations showed that P(phosphor) accepted electron from Co(cobalt) in single-P (Co_2P (2), Co_3P (1) and Co_4P (2)) cluster models, which agrees well with the Pauli electronegative rule, and a very strong interaction between Co and P resulted in formation stable clusters Co_2P (2), Co_3P (1) and Co_4P (2). However, two-P (Co_nP_2) cluster models and single-P cluster Co_5P (1) were unstable, and it was impossible to present direct P-P contact in two-P (Co_nP_2) cluster models. It could be concluded that the clusters Co_2P (2), Co_3P (1) and Co_4P (2) is more reasonable to represent the local structure of Co-P amorphous alloy.