# Excited states using ORMAS flag in GAMESS

I am trying to calculate the excited states using single reference CISD on $$\ce{CH3OH},$$ using ORMAS' CI-X option in GAMESS. As a test example I am using the $$\ce{CH3OH}$$ that has 2 core, 7 occ. valence, 39 empty MOs (50 AOs, 48 MOs). I am unable to understand the $ormas flag in the following ormas-meoh-cisd.inp file: ! single reference CISD on CH3OH, using ORMAS' CI-X option. ! counting: 2 core, 7 occ. valence, 39 empty MOs (50 AOs, 48 MOs) ! the resulting CI-SD has 53,964 Sz=0 A' determinants ! $$contrl scftyp=rhf cityp=ormas runtyp=energy ispher=1$$end $$system mwords=50$$end $$basis gbasis=ccd$$end $$guess guess=huckel$$end $$scf dirscf=.true.$$end $$trans dirtrf=.true.$$end $$cidet group=Cs stsym=Ap ncore=2 nact=46 nels=14 nstate=3$$end $$ormas nspace=2 mstart(1)=3,10 mine(1)=12,0 maxe(1)=14,2$$end$data
Methanol...CISD...RHF/6-31G(d) geometry
Cs

H     1.0  -1.0616171503   0.8036449245   0.0000000000
O     8.0  -0.6870131482  -0.0653470836   0.0000000000
C     6.0   0.7093551399   0.0291827007   0.0000000000
H     1.0   1.0836641283   0.5408321444   0.8835398105
H     1.0   1.0975386849  -0.9797829903   0.0000000000
$end  The following keywords are used in the $ORMAS section:

nspace=2
mstart(1)=3,10
mine(1)=12,0
maxe(1)=14,2


I can understand the nspace = 2 means the active space is partitioned into doubly occupied + active and valence orbitals. However, I don't understand how the numbers pertinent to the rest of the flags in \$ORMAS are chosen. Any explanation would be really helpful and appreciated.

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