TOMBO Ver.2 Manual

3.2 INPUT.inp 33
O : 1s 2
There is only one s orbital, so the number is 1 for s orbital.
In rutile TiO 2 , 9 × 2 + 1 × 4 = 22, sothat ncs = 22.
3.2.15 ncc
Number of core constituents.
"ncc" is the number of core constituents to be excluded from the Fock exchange in HF
and GW calculations. For the intermediate states in the calculation of the exchange term,
the states from “number of core constituents” (ncc) + 1 to “number of occupied states” (noc)
are used in the code. Deep core states also contribute largely to the exchange term, so that
"ncc" should be usually set at 0 [default].
3.2.16 nol
Number of levels.
"nol" is the number of levels (states) to be included in the GW calculations of the correlation
parts (the polarization function and the self-energy). Default value for iSblp is 300.
Note: If "nol" is not enough, it leads band gap become large.
Note: "nol" must be less than the number of basis set (functions) "nbs". The value of
"nbs" can be found in "OUTPUT.out" file.
3.2.17 nband
Number of empty states to display in GWA.out.
"nband" is the number of output empty levels (band), i.e., the number of empty states in
conduction bands to be displayed in GW (GWA.out). Default is nband = 0.
3.2.18 q_eliminate
Criterion to remove AO.
AO is eliminated, if truncated AO has norm less that "q_eliminate". For example, if
one sets q_eliminate = 0.001 as small enough, no AO will be removed from the basis set.
The default value of q_eliminate is 0.3, if the unit cell size is less than 4.0 Å, and 1 × 10 −2
otherwise.
3.2.19 q_min_mod
Criterion to truncate AOs.