Since the exact mechanism of superconductivity has not been completely understood yet, investigating this phenomenon is of great interest. Here, we first studied CuO₂ and La₂O₂ monolayers separately and then investigated the changes in the electronic structure of the layered La₂CuO₄ as formed by stacking those monolayers together. The results showed that when the two layers are sandwiched in tandem, a charge transfer mechanism occurs initially from La₂O₂ to CuO₂. This charge transfer mechanism results in localized orbitals that contribute to the bonds in CuO₂, making them stronger. On the other hand, Cu dz2 orbitals move toward the Fermi level, being more delocalized. This phenomenon occurs by changing the crystal field effect on Cu atoms and creating the octahedral coordination of O atoms around Cu atoms. Therefore, due to the crystal field effect, the energy level of dz2 orbitals, which lie under those of dxz + dyz and dxy orbitals, ascend and lie under the energy level of dx2y2 orbitals. These changes in the electronic structure create a half-filled band around the Fermi level consisted of Cu dx2y2 and dz2 orbitals and apical O Pz orbitals. This configuration occurs by emptying the states due to La₂O₂ near the Fermi level and occupying the states due to CuO₂, lowering the bands in energy. The lowering separates the band around the Fermi level from other bands.

由于尚未完全了解超导的确切机理，因此对此现象的研究引起了极大的兴趣。在这里，我们首先分别研究了CuO ₂和La ₂ O ₂单层，然后研究了通过将这些单层堆叠在一起而形成的La ₂ CuO ₄层的电子结构的变化。结果表明，当两层串联时，电荷转移机制最初从La ₂ O ₂到CuO _2发生。该电荷转移机制导致局部轨道，该轨道有助于CuO _2中的键，使它们更坚固。另一方面，Cu dz2轨道向费米能级移动，被更局域化。这种现象是通过改变对Cu原子的晶体场效应并在Cu原子周围创建O原子的八面体配位而发生的。因此，由于晶体场效应，处于dxz + dyz和dxy轨道之下的dz2轨道的能级上升，并且处于dx2y2轨道的能级之下。电子结构的这些变化在费米能级附近形成了一个半填充带，该带由Cu dx2y2和dz2轨道以及顶O Pz轨道组成。通过排空费米能级附近的La ₂ O ₂所致的状态并占据CuO ₂所致的状态来进行这种配置，降低能量带。降低使费米能级附近的频带与其他频带分开。