Welcome to the Diamond test system.

This example studies a C vacancy in Diamond in the -2 charge
state. The complete electrostatic correction for this system 
involves computing the following terms 
(see Eqn 2, Eqn 3 and Eqn 4 in CoFFEE paper):

1. Lattice correction term: E^{lat}, obtained from the
   model calculations.
   The details on computing E^{lat} are provided in 
   the folder Model_Scaling/
2. Potential alignment term: -\Delta V_{q/0}, Eqn 5
   in the paper.
   The details on computing this term are provided in 
   the folder PA_q0/
3. Potential alignment term: -q\Delta V_{0/p}, Eqn 2
   in the paper.
   The details on computing this term are provided in
   the folder PA_0p/

Complete correction for the 4x4x4 super cell,
E_corr = E^{lat} + (-\Delta V_{q/0}) + (-q\Delta V_{0/p})
E_corr = 0.97 + 0.0 + 0.1 eV 
E_corr = 1.07 eV


For the 4x4x4 super cell:
Uncorrected formation energy: 13.189 eV
Corrected formation energy: 14.259 eV

The QE_input/ directory provides the 
Quantum Espresso input file for the 4x4x4
super cell calculation with a C 
vacancy in the -2 charged state.
We also provide the carbon pseudopotential.
