CuB2O4晶體在第一原理的研究

Abstract

研究CuB2O4反鐵磁性材料在第一原理中的能帶架構以及材料特性。 CuB2O4在第一原理中，使用六個單元的方式呈現週期性的結構分布，在這個晶格中a=11.357、c=5.542 Å, k-mesh使用4x4x4, nbands為400 並且使用VASP GGA+U的方法，其中Cu(A)&Cu(B)的U分別為U1=6.4eV, U2=7.0eV。 在計算中，我們發現CuB2O4的density of state(DOS)在導帶的地方會出現兩個非常明顯的尖點。一個是由Cu(A)&O(1)組成，另外一個則是由Cu(B)&O(2)&O(3)&O(4)所貢獻，因此我們希望可以分析出兩者的不同。

Ab initio study of anti-ferromagnetic non-collinear CuB2O4 crystal ,CuB2O4 crystallizes in first-principles calculations, with six formula units were performed using periodic density function theory. The cell of dimensions a=11.357 and c=5.542 Å, k-mesh=4x4x4, nbands=400 and use GGA+U on VASP where U1=6.4eV, U2=7.0eV for Cu(A)&Cu(B).In the case, we found that CuB2O4’s density of state(DOS) has two peaks in conduction band. One is contributed by Cu(A) & O(1), the other one is contributed by Cu(B) & O(2) & O(3) & O(4). As the result of, we can sort atoms to two types. A type is Cu(A) and O(1) which donate states to peak(1), the other type is Cu(B) and O(2)&O(3)&O(4) which donate states to peak(2). And we could do analyze their difference.