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[交流] 【求助】怎么计算Al2O3的状态方程

现在做分子动力学，希望对比一下VASP优化计算Al2O3的状态方程。前面也看过几个计算状态方程的较为简单的例子，现在对VASP刚接触，不知道这种晶格Al2O3的POSCAR该怎么写？设置KPOINTS中对于Al2O3需要注意什么？INCAR都需要那些参数？
有的说对于非立方晶系还要考虑压强,该怎么弄呢？请高手指点一下？

Al2O3的cif文件如下：

#### CIF created by Crystallographica 2 ####

data_AluminiumOxideAlpha

_audit_creation_method                   'Crystallographica 2'
_cell_angle_alpha                      90
_cell_angle_beta                         90
_cell_angle_gamma                      120
_cell_formula_units_Z                   6
_cell_length_a                         4.7602
_cell_length_b                         4.7602
_cell_length_c                         12.993
_cell_volume                            254.971
_cgraph_comments                      'Recovering experimental and theoretical electron densities    in corundum using the multipolar model : IUCr multipole    refinement project '
_cgraph_title                         'Aluminium Oxide - Alpha'
_chemical_formula_sum                   'Al2 O3'
_symmetry_space_group_name_H-M          'R -3 c'
_symmetry_space_group_name_Hall       '-R 3 2"c'

loop_
      _symmetry_equiv_pos_as_xyz
      'x, y, z'
      'x-1/3, y+1/3, z+1/3'
      'x+1/3, y-1/3, z-1/3'
      '-x, -y, -z'
      '-x-1/3, -y+1/3, -z+1/3'
      '-x+1/3, -y-1/3, -z-1/3'
      '-y, x-y, z'
      '-y-1/3, x-y+1/3, z+1/3'
      '-y+1/3, x-y-1/3, z-1/3'
      'y, -x+y, -z'
      'y-1/3, -x+y+1/3, -z+1/3'
      'y+1/3, -x+y-1/3, -z-1/3'
      '-x+y, -x, z'
      '-x+y-1/3, -x+1/3, z+1/3'
      '-x+y+1/3, -x-1/3, z-1/3'
      'x-y, x, -z'
      'x-y-1/3, x+1/3, -z+1/3'
      'x-y+1/3, x-1/3, -z-1/3'
      'x-y, -y, -z+1/2'
      'x-y-1/3, -y+1/3, -z-1/6'
      'x-y+1/3, -y-1/3, -z+1/6'
      '-x+y, y, z+1/2'
      '-x+y-1/3, y+1/3, z-1/6'
      '-x+y+1/3, y-1/3, z+1/6'
      '-x, -x+y, -z+1/2'
      '-x-1/3, -x+y+1/3, -z-1/6'
      '-x+1/3, -x+y-1/3, -z+1/6'
      'x, x-y, z+1/2'
      'x-1/3, x-y+1/3, z-1/6'
      'x+1/3, x-y-1/3, z+1/6'
      'y, x, -z+1/2'
      'y-1/3, x+1/3, -z-1/6'
      'y+1/3, x-1/3, -z+1/6'
      '-y, -x, z+1/2'
      '-y-1/3, -x+1/3, z-1/6'
      '-y+1/3, -x-1/3, z+1/6'

loop_
      _atom_site_label
      _atom_site_type_symbol
      _atom_site_fract_x
      _atom_site_fract_y
      _atom_site_fract_z
      _atom_site_U_iso_or_equiv
      _atom_site_thermal_displace_type
      _atom_site_occupancy
      Al1 Al3+ 0 0 0.35217 0 Uani 1
      O1 O2- 0.30634 0 0.25 0 Uani 1

loop_
      _atom_site_aniso_label
      _atom_site_aniso_U_11
      _atom_site_aniso_U_22
      _atom_site_aniso_U_33
      _atom_site_aniso_U_12
      _atom_site_aniso_U_13
      _atom_site_aniso_U_23
      Al1 0.00255 0.00255 0.00266 0.00128 0 0
      O1 0.00305 0.00305 0.0035 0.00153 0.00034 0.00068

_eof

#### End of Crystallographic Information File ####

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