摘要
采用密度泛函理论的第一性原理平面波超软赝势,并用广义梯度近似、Perdew-Wang 91函数处理交换关联势的方法计算了在HfC超晶胞中掺入Cr、Al后的三元复合物(Hf_(1-x)Cr_xC、Hf_(1-x)Al_xC,x=0-1)的晶体结构和电子性质,并就形成能讨论其相对稳定性。结果显示掺杂量增多,复合物的形成能增加,稳定性降低,当Cr、Al的量分别小于63%、55%时复合物最稳定,掺Cr的稳定性优于掺Al,Cr有较多的d电子参与杂化成键,且成键作用强,使C-Cr键的共价性、金属性比C-Al键强。
The first-principle was used to calculate the crystal structures, electronic properties and to predict the relative stabilities of Hf1-xCrxC, Hf1-xAlxC （x =0- 1 ）. The calculation was based on density functional theory and the generalized gradient approximation （ GGA）, Perdew-Wang 91 function was used for the exchange and correlation potential. The results show that the energy of formation of these ternary compounds increased with the Cr and A1 content being increased, and then the compounds stabilities decrease. The compounds can exist stably while the content of Cr, A1 is up to 63%, 55%, respectively. And Hf1-xCrxC is more stable than H1-xAlxC. According to the density of states, the covalent and metallic bonds between C and Cr are stronger than those between C and A1 because more d electrons in Cr are hybridized.
出处
《计算机与应用化学》
CAS
CSCD
北大核心
2009年第5期641-644,共4页
Computers and Applied Chemistry
