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专业: 凝聚态物性 II ：电子结构

[求助] 请问siesta计算BornCharge时为什么输出的张量不满足对称性要求呢？谢谢

我测试siesta，计算立方相BaTiO3的波恩有效电荷，结果输出的张量中分量很多啊，立方晶每个原子的有效电荷应该只有一个分量啊，另外，立方BaTiO3的三个O原子应该是等价的啊，为什么计算出的有效电荷不一样呢？
感激不尽！求指教！
输入文件如下：

SystemName Barium titanate (BaTiO3) cubic structure
SystemLabel batio3
NumberOfSpecies 3
NumberOfAtoms 5
%block ChemicalSpeciesLabel
   1    56    Ba
   2    22    Ti
   3    8    O
%endblock ChemicalSpeciesLabel

%block PS.lmax
Ba 3
Ti 3
O 3
%endblock PS.lmax

PAO.BasisType split
%block PAO.Basis
Ba 5    0.70
n=5 0 1 E    98.95    5.90
6.39899920099572
1.00000000000000
n=6 0 2 E    97.95    6.50
6.99956358549850       5.99949655050583
1.00000000000000       1.00000000000000
n=5 1 1 E    96.95    6.09
6.59922580635556
1.00000000000000
n=5 2 1 E    95.95    6.60
7.09995685034315
1.00000000000000
n=6 1 1 E    94.96    6.60
7.09996103032325
1.00000000000000
Ti 5    1.91
n=3 0 1 E    93.95    5.20
5.69946662616249
1.00000000000000
n=3 1 1 E    95.47    5.20
5.69941339465994
1.00000000000000
n=4 0 2 E    96.47    5.60
6.09996398975307       5.09944363262274
1.00000000000000       1.00000000000000
n=3 2 2 E    46.05    4.95
5.94327035784617       4.70009988294302
1.00000000000000       1.00000000000000
n=4 1 1 E    0.50    1.77
3.05365979938936
1.00000000000000
O    3    -0.28
n=2 0 2 E    40.58    3.95
4.95272270428712       3.60331408800389
1.00000000000000       1.00000000000000
n=2 1 2 E    36.78    4.35
4.99990228025066       3.89745395068600
1.00000000000000       1.00000000000000
n=3 2 1 E    21.69    0.93
2.73276990670788
1.00000000000000
%endblock PAO.Basis

LatticeConstant    7.57 bohr
%block LatticeVectors
  1.00  0.00  0.00
  0.00  1.00  0.00
  0.00  0.00  1.00
%endblock LatticeVectors

AtomicCoordinatesFormat Fractional
%block AtomicCoordinatesAndAtomicSpecies
  0.00  0.00  0.00       1
  0.50  0.50  0.50       2
  0.00  0.50  0.50       3
  0.50  0.00  0.50       3
  0.50  0.50  0.00       3
%endblock AtomicCoordinatesAndAtomicSpecies

%block kgrid_Monkhorst_Pack
6  0  0  0.5
0  6  0  0.5
0  0  6  0.5
%endblock kgrid_Monkhorst_Pack

MeshCutoff          200 Ry
DM.NumberPulay       3
DM.UseSaveDM          F
DM.MixingWeight       0.0200    # New DM amount for next SCF cycle
DM.Tolerance          1.d-4    # Tolerance in maximum difference
                                 # between input and output DM
DM.NumberKick       15
DM.KickMixingWeight 1.000
ElectronicTemperature  100 K
MaxSCFIterations    400

MD.TypeOfRun FC
MD.FCDispl 0.04 Bohr

BornCharge T
%block PolarizationGrids
7  3  3
3  7  3
3  3  7
%endblock PolarizationGrids

WriteCoorStep    .true.
WriteForces       .true.

计算的有效电荷如下：

BC matrix
   2.2565879    0.0000003    0.0000000
   0.0002761    2.2586398    -0.0000013
   -0.0000002    0.0003220    2.2587290
   7.0653476    -0.0000006    0.0000283
   -0.0000712    7.0646728    -0.0000014
   -0.0000002    0.0000143    7.0650252
   -5.4552768    -0.0000003    -0.0001544
   0.0000997    -1.9375166    0.0000012
   -0.0000020    0.0000339    -1.9375039
   -1.9375306    -0.0000008    0.0000191
   -0.0000036    -5.4553489    -0.0000027
   0.0000038    0.0000020    -1.9376244
   -1.9376920    0.0000007    -0.0000649
   -0.0000915    -1.9377835    -0.0000031
   -0.0000028    -0.0000270    -5.4563491
这个我觉得应该是没三行属于相同的原子的，因为有效电荷是二阶张量

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