# O3 molecule in a big box

# the unit cell
 acell 10 10 10    
# lengths of the primitive vectors (in Bohr)


# the atom types 
ntypat 1          
# only one type of atom
 znucl 8           
# The pseudopotential(s) 
                  
# mentioned in the "files" file must correspond
                  
# to the type(s) of atom. Here, the only type is Oxygen.
                         


# Definition of the atoms 
natom 3           
# There are three atoms 
typat 1  1  1        
# The keyword indicates the Euclidean location of the atoms xcart
                  
# in Bohr  -1.4  0.0  0.0
# in Bohr
   1.4  0.0  0.0 
# in Bohr   0.0  0.0  1.2 

# Definition of the planewave basis set 
ecut 10.0         
# Maximal plane-wave kinetic energy cut-off, in Hartree


# Definition of the k-point grid
 nkpt 1            
# Only one k point is needed for isolated system,
                  
# taken by default to be 0.0 0.0 0.0 


# Definition of the SCF procedure 
nstep 10          
# Maximal number of SCF cycles 
toldfe 1.0d-6     
# Will stop when, twice in a row, the difference 
                  
# between two consecutive evaluations of total energy 
                  
# differ by less than toldfe (in Hartree) 
diemac 1.0        
# Although this is not mandatory, it is worth to
                  
# precondition the SCF cycle. The model dielectric 
diemix 0.5        
# function used as the standard preconditioner
                  
# is described in the "dielng" input variable section.
                  
# Here, we follow the prescriptions for molecules 
                  
# in a big box