关注：

1) Raman光谱

2) 超导温度计算

摘录：

红外与Raman：与电荷极化有什么关系？  与原子振动之间的关系

Spin polarization was included in all calculations. In the antiferromagnetic (AFM) calculations, we used the collinear 1-k AFM structure where the atomic spin moment was along the [001] direction. 

Phonons and Raman scattering were carried out using the direct method [21]as implemented in the PHONON code[22]. 

The visualization of electron-structure-calculation data was generated by using the program wxDragon [23]. The crystal structures were drawn by VESTA package[24].

In this subsection, we first focus on the ionic Born effective charges   , which can be used to interpret the change on electronic polarizationcaused by the ionic displacement, and the form, for a particular atom in the lattice,is determined by the symmetry of its position [54]

Eigen-displacements for each type of optical vibrational modes and frequencies at the Γ point are depicted in Figure 8.

U值计算对能量的影响

we calculated the thermodynamic properties (the entropy S, the constant-volume specific heat C_V) for U_eff ranging from 4 to 6 eV for CeGaO₃ and from 3 to 5 eV for PuGaO₃. We found an energy difference of only 0.5J/(K×mol) between these extremes, indicating a weak dependence upon U. 

取巧vs不取巧，仅仅电子结构采用HSE或GW

Only band structures were evaluated by both PBEsol + U and the HSE06 [36], the latter giving a better description of the band gaps in semiconductors. Pure PBEsol calculations are carried out on the Ga and Ga₂O₃.

To perform an accurate description of electronic properties, we employ the PBEsol+U and HSE06 approaches to optimize equilibrium geometries and band gap for Pnma PuGaO₃ and CeGaO₃ in ferromagnetic and AFM configurations, as shown in Table 2.

HSE只是针对电子结构精修；是否存在HSE+U的计算设置？可核实下

力学常数计算

The mechanical stability is an essential factor for a crystal to exist[44]. To evaluate the mechanical properties of AGaO₃ () in Pnma phase at ambient pressure, calculated elastic constants are given in Table 1 by using the strain-stress relationship[45]. 

The key criteria for mechanical stability of a crystal are that the strain energy must be positive, which implies that the elastic constants should satisfy the generalized elastic stability criteria. The Pnma phase is an orthorhombic structure, which has nine independent elastic constants C₁₁, C₂₂, C₃₃, C₄₄, C₅₅, C₆₆, C₁₂, C₁₃ and C₂₃, and the corresponding mechanical stability criteria are given by[46]

From the elastic constants listed in Table 1, we find that the Pnma phases satisfy their respective mechanical stability criteria at ambient pressure, thus confirming their mechanical stability. Combining the results of thermodynamic, lattice dynamical, and mechanical stability, we conclude that orthorhombic Pnma phase is the ground-state structure for both PuGaO₃ and CeGaO₃ at ambient pressure.

电子结构计算

we first carry out the systematic calculations of the fat-band dispersions, partial densities of states (PDOS) and COHP analysis, as shown in Figure 5. We can see that XGaO₃ display direct band gaps with the band gap of 2.76 eV. 

非键是什么状态

http://blog.sciencenet.cn/home.php?mod=space&uid=567091&do=blog&quickforward=1&id=797400

http://blog.sciencenet.cn/home.php?mod=space&uid=567091&do=blog&id=796757

.-pCOHP<0  反键区域，-pCOHP>0，成键区域，费米能级向上(反键区域）移动，材料失稳；反之，材料稳定性增加。

The transition from bonding to antibonding character occurs at E ≈ -5 eV. Between E≈-3 eV and E ≈ 3 eV, nonbonding states are present, and the antibonding states are found above E ≈ 3 eV. A slightly large value of COHP for Ga-O1 shows that the Ga-O2 interactions are not as strong as the Ga-O1interactions. These bonding states of the occupied crystal orbitals reveal extensive mixing between Pu-O and Ga-O chemical bonding in the Pnma structure.

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