add - creating the configuration list
The add program constructs a list of configurations to define the CI space by exciting electrons from a set of reference configurations to a set of active non-relativistic shells. It takes in the input file ADD.INP, which specifies the reference configurations, active non-relativistic shells, and minimum and maximum occupation numbers of each shell. It writes the file CONF.INP, which includes a list of user-defined parameters and the list of configurations constructed by exciting electrons from a list of basic configurations.
The following is a sample input ADD.INP file. Each line has a description of the respective variable. The third block starting with 4f 9 14 is a list of the orbitals and minimum and maximum occupation numbers. For example, 4f 9 14 refers to having a minimum of 9 electrons or a maximum of 14 electrons for the 4f orbital.
Ncor= 4 !# number of basic configurations. Must match the list below.
NsvNR 16 !# number of active NR shells. The list below may be longer.
mult= 2 !# multiplicity of excitations. For full CI use mult=Ne
NE = 14 !# number of valence electrons
L: 4f14 !# list of basic configurations
L: 4f13 5p1 !# from which electrons are excited from.
L: 4f12 5s2 !# the number of configurations listed here
L: 4f11 5s2 5p1 !# must match the number on the first line 'Ncor= 4'
nnlee nnlee nnlee !# formatting of configurations
!# the numbers nn refer to the principal quantum number
!# the letters l refer to the angular momentum quantum number
!# the numbers ee refer to the occupation of that orbital
4f 9 14 5s 0 2 5p 0 3 5d 0 2 5f 0 2 5g 0 2
6s 0 2 6p 0 2 6d 0 2 6f 0 2 6g 0 2 7s 0 2
7p 0 2 7d 0 2 7f 0 2 7g 0 2
##nnl ee ee nnl ee ee nnl ee ee nnl ee ee nnl ee ee nnl ee ee
>>>>>>>>>>>>> Head of the file CONF.INP >>>>>>>>>>>>>>>>>>>>>>>>
Ir17+_even # ion_parity
Z = 77.0 # atomic number
Am = 192.0 # atomic weight
J = 4.0 # total angular momentum
Jm = 4.0 # angular momentum projection
Nso= 14 # number of closed core shells
Nc = 10 # number of relativistic configurations (ignored in add program)
Kv = 4 # Kv = (3 - use projections, 4 - no projections)
Nlv= 5 # number of energy levels
Ne = 14 # number of valence electrons
Kl4= 1 # Kl4 = (1 - initial approx. from energy matrix, 2 - initial approx. from CONF.XIJ file)
Nc4= 20 # number of relativistic configurations in initial approximation
Gj = 0.0000 #
Crt4= 0.0001 # cutoff criteria for davidson convergence
kout= 0 # key for level of output (0 - low detail output, 1 - detailed output)
Ncpt= 0 # number of relativistic configurations in PT block (ignored in add program)
Cut0= 0.0001 # cutoff criteria for weights of PT configurations
N_it= 100 # number of davidson iterations
Kbrt= 1 # key for Breit (0 - Coulomb, 1 - Gaunt, 2 - Full Breit)
Gnuc= 1.07 # gyromagnetic ratio
0.1002 0.2002 -0.2102 0.2104 0.3002 -0.3102
0.3104 -0.3204 0.3206 0.4002 -0.4102 0.4104
-0.4204 0.4206
Note
The second block listing the basic configurations has a specific formatting __nnlee__, where __ indicate spaces, nn is the principal quantum number, l is the angular momentum quantum number as a letter (s=0, l=1, d=2, …), and ee is the number of electrons in that orbital.
Note
The order in which the configurations and basis orbitals must be listed identically with those from BASS.INP.