script file
  alat=" 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0"
  for i in $alat;
  do
   echo $i
   mkdir $i
   lattice="`echo $i`";
   sed "s/AAA/$lattice/g"  fireball.sample > fireball.in;
   ./runTG.com > a-$i.out
   grep "etot/atom" a-$i.out | cut -b50-65
   mv CHARGES $i/
   mv a-$i.out $i/
  done

fireball.sample

  &OPTION
  basisfile = C1.bas
  lvsfile = C1.lvs
  kptpreference = C1.32.kpts
  nstepf = 1
  ifixcharge = 0
  iqout = 1
  rescal = AAA
  &END
  &OUTPUT
  iwrteigen = 1
  &END

atomic coordinates are defined in **C.bas** file C¹(0.0, 0.0) and C²(√3/3, 0.0):
        2
  6  0.0000000  0.00000000  0.00000000
  6  0.57735027 0.00000000 0.00000000

lattice vector a1(√3/2, 0.5); a2(√3/2, -0.5):

  0.8660254   0.5000000   0.00000000
  0.8660254  -0.5000000   0.00000000
  0.00000000  0.00000000  60.00000000

The full Brillouine Zone (BZ) was sampled by 8x8 (Monkhorst-Pack grid). But for the energy optimization just Irreducible BZ (IBZ( is needed. In this case applying inversion symmetry we will get 32 k-points from 64 k-points for sampling the IBZ.
The SCF solution has been obtained using 32 k-points, in file C1.32.kpts:

            32
   -3.17414904    0.00000000    0.00000000           0.03125000
   -2.72069907   -0.78539819    0.00000000           0.03125000
   -2.26724935   -1.57079637    0.00000000           0.03125000
   -1.81379938   -2.35619450    0.00000000           0.03125000
   -1.36034954   -3.14159274    0.00000000           0.03125000
    2.72069911    2.35619441    0.00000000           0.03125000
    3.17414895    1.57079641    0.00000000           0.03125000
    3.62759880    0.78539840    0.00000000           0.03125000
   -2.72069907    0.78539819    0.00000000           0.03125000
   -2.26724935    0.00000000    0.00000000           0.03125000
   -1.81379938   -0.78539819    0.00000000           0.03125000
   -1.36034954   -1.57079637    0.00000000           0.03125000
   -0.90689969   -2.35619450    0.00000000           0.03125000
   -0.45344985   -3.14159274    0.00000000           0.03125000
    0.00000000   -3.92699099    0.00000000           0.03125000
   -3.17414895    1.57079641    0.00000000           0.03125000
   -2.26724935    1.57079637    0.00000000           0.03125000
   -1.81379938    0.78539819    0.00000000           0.03125000
   -1.36034954    0.00000000    0.00000000           0.03125000
   -0.90689969   -0.78539819    0.00000000           0.03125000
   -0.45344985   -1.57079637    0.00000000           0.03125000
    0.00000000   -2.35619450    0.00000000           0.03125000
    0.45344985   -3.14159274    0.00000000           0.03125000
   -2.72069911    2.35619441    0.00000000           0.03125000
   -1.81379938    2.35619450    0.00000000           0.03125000
   -1.36034954    1.57079637    0.00000000           0.03125000
   -0.90689969    0.78539819    0.00000000           0.03125000
   -0.45344985    0.00000000    0.00000000           0.03125000
    0.00000000   -0.78539819    0.00000000           0.03125000
    0.45344985   -1.57079637    0.00000000           0.03125000
    0.90689969   -2.35619450    0.00000000           0.03125000
    1.36034954   -3.14159274    0.00000000           0.03125000
The total energy vs. the lattice parameter is plotted here: