• Quantum-espresso类似于vasp，计算材料性质同样可以分为以下几步：

    （1）优化（relax和vc-relax）-获得能量最低构型；

    （2）自洽（scf）-获得体系基态电荷密度+波函数+构型能量；

    （3）非自洽（nscf）-固定K点及利用基态电荷密度，获得DOS；

    （4）性质计算；

  The format of namelist and input_card as input files under PWscf calculations：

   There are three mandatory namelist in PWscf. 

          &CONTROL &SYSTEM &ELECTRONS;

    There are additional naelists in PWscf that must be specified under certain circumstances.  

      (1) &IONS: needed when Atoms move! (relax and MD)

      (2) &CELL：needed when CELL move! (vc-relax and vc-MD)

    There are three mandatory input_cards in PWscf:

       ATOMIC_SPECIES: ATOMIC_POSITIONS: K_POINTS;

    there are additional input_cards in PWscf that must be specifed only under certain circumstances.

      (1) CELL_PARAMETERS  (only for ibrav=0 in &SYSTEM)

      (2) OCCUPATIONS      (only for occupations='fixed' &ELECTRONS)

      (3) CLIMBING_IMAGES  (only for NEB calculations)

      (4) CONSTRAINTS      (only for constrained dynamics)

      (5) COUECTVE_VARS    (only for metadynamics)