We generate some numerical atomic orbitals
xatom -s O -nao -latter off -file_nao O.nao -N 100
xatom -s H -nao -latter off -file_nao H.nao -N 100
These commands invoke an atomic electronic structure calculation for atomic oxygen and hydrogen. The options "-nao" and "-file_nao O.nao" are used to store the radial orbital function in the file O.nao. A total number of 100 radial grid points is used ("-N 100") and we do not emply the Latter correction. For more details, please consider the xatom manual.
The input file specifies the geometry and the numberical atomic orbital basis set
O 0.000000000000 -0.125549913844 0.000000000000 2s1p O.nao
H -1.423436754553 0.996284121013 0.000000000000 1s H.nao
H 1.423436754553 0.996284121013 0.000000000000 1s H.nao
The command
xmolecule input.in -o output.out
calculates neutral ground state water employing the Hartree-Fock-Slater method. The output of the calculation is printed in the file output.out. If "-o output.out" is omitted, calculation results are printed (standard out).
We generate now numerical atomic orbitals for core ionized oxygen:
xatom -s O -nao -latter off -file_nao O1s.nao -N 100 -hole 1s1 -transition auger -file_auger O1s.auger
The additional option "-hole 1s1" invokes the computation of a K hole state. By using the option "-transition auger -file_auger O1s.auger" additional information of Auger radial matrix elements are printed into the file O1s.auger. These values are used by xmolecule to compute Auger transitions.
We employ those in the input file and add options for the molecular electronic configuration and trigger Auger-Meitner decay calculations:
O 0.000000000000 -0.125549913844 0.000000000000 2s1p O1s.nao
H -1.423436754553 0.996284121013 0.000000000000 1s H.nao
H 1.423436754553 0.996284121013 0.000000000000 1s H.nao
auger=yes
occ=12222
The command
xmolecule input.in -o output.out
calculates now the electronic structure for the core-ionized water molecule and calculated Auger-Meitner decay rates.
The input file specifies the geometry and the numerical atomic orbital basis set
O 0.000000000000 -0.125549913844 0.000000000000
H -1.423436754553 0.996284121013 0.000000000000
H 1.423436754553 0.996284121013 0.000000000000
gto=6-31G
HF=yes
xmolecule input.in -o output.out
makes a Hartree-Fock calculation on water.
With
xatom -silent -latter off -s O -hole 1s1 -N 100 -nao -file_nao O.nao \
-transition auger -file_auger O.auger
we provide the Auger-Meitner Matrix elements and numeric atomic orbitals for the oxygen atom.
Running
xmolecule input.in -occ 12222 -auger
calculates the core ionized state of water using restricted open-shell Hartree Fock and calculates Auger-Meitner processes (energies are based on orbital energy differences)
Running
xmolecule input.in -occ 12222 -auger -fluorescence -process_CIS -nstates 100 -o output.out
computes Auger-Meitner and fluorescence decays employing configuration interaction based on a three-valence-hole-one-particle scheme.
xatom -N 50 -rmax 30. -latter off -s C -nao -file_nao C.nao \
-transition transitiondipole -file_tdipole C.tdipole -PE_start 10 -PE_end 1000 -PE_dE 2.0
xatom -N 50 -rmax 30. -latter off -s O -nao -file_nao O.nao \
-transition transitiondipole -file_tdipole O.tdipole -PE_start 10 -PE_end 1000 -PE_dE 2.0
In the atomic electronic structure calculations, we now provide the additional command line parameters "-file_tdipole O.tdipole -PE_start 10 -PE_end 1000 -PE_dE 2.0". They invoke the computation of transition diplole matrix elements for the atom employing an energy grid for the electronic continuum starting at 10 eV up to 1000 eV with 2.0 eV steps. These values have to be adapted to cover the expected molecular photoelectron energy.
input file:
C 0.0 0.0 0.0 2s1p C.nao
O 0.0 0.0 1.128 2s1p O.nao
unit=angstrom
gto=6-31G
The command
xmolecule input.in -HF -pcs -PE 1000 -o output.out
computes photoionization cross sections at photonenergy 1000eV based on orbital energies.
The command
xmolecule input.in -HF -pcs -PE 1000 -process_CIS
computes K-shell photoionization cross sections at photonenergy 1000eV based on configuration interaction employing a one-core-hole--one-valence-hole--one-virtual-particle scheme.
The command
xmolecule input.in -HF -CIS -gradient -state 2 -nstates 10
computes the second excited states employing configuration-interaction singles, its gradients and non-adiabatic couplings to the other 10 states
The command
xmolecule input.in -HF -CIS -state 2 -absorption
computes the absorption of the second excited CIS states employing configuration-interaction singles.