use ../dir_00054 and ../test_dir_00030 to compute the cohesive energy

grep "!    total" ../test_dir_00030_Cu_bulk_equilibrium_Ecut350_K16/pwscf.log
!    total energy              =    -392.49457196 Ry
grep "!    total" ../dir_00054_Cu_myPPs_V01_spinPol/pwscf.log 
!    total energy              =    -392.23481125 Ry

(392.23481125-392.49457196)/2*627.51
= -81.50122156605 kcal/mol