$cell vectors
1.0
  4.1999980237245627    0.0000000000000000    0.0000000000000000
  0.0000000000000000    4.1999980237245627    0.0000000000000000
  0.0000000000000000    0.0000000000000000    7.9599962544875025
 1 3 1
Direct
  0.0000000000000000    0.0000000000000000    0.0000000000000000 # Hg1
  0.5000000000000000    0.5000000000000000    0.0000000000000000 # Cl1
  0.0000000000000000    0.0000000000000000    0.2943999999999997 # Cl2
  0.0000000000000000    0.0000000000000000   -0.2943999999999997 # Cl3
  0.5000000000000000    0.5000000000000000    0.4999999999999997 # N1
