done some cleaning in the casscf and added a detailed example of Mult…

…i state CASSCF

src/casscf_cipsi/README.rst

@@ -4,13 +4,15 @@ casscf
 
 |CASSCF| program with the CIPSI algorithm.
 
-Example of inputs
------------------
+
+Example of inputs for GROUND STATE calculations
+-----------------------------------------------
+NOTICE :: FOR EXCITED STATES CALCULATIONS SEE THE FILE "example_casscf_multistate.sh"
 
 a) Small active space : standard CASSCF 
 ---------------------------------------
 Let's do O2 (triplet) in aug-cc-pvdz with the following geometry (xyz format, Bohr units)
-3
+2
 
  O           0.0000000000        0.0000000000       -1.1408000000
  O           0.0000000000        0.0000000000        1.1408000000
@@ -45,3 +47,4 @@ qp set casscf_cipsi small_active_space False
 qp run casscf | tee ${EZFIO_FILE}.casscf_large.out
 # you should find around -149.9046
 
+

src/casscf_cipsi/casscf.irp.f

@@ -54,14 +54,24 @@ subroutine run
 
     call write_time(6)
     call write_int(6,iteration,'CAS-SCF iteration = ')
-    call write_double(6,energy,'CAS-SCF energy = ')
+    call write_double(6,energy,'State-average CAS-SCF energy = ')
 !    if(n_states == 1)then
 !     call ezfio_get_casscf_cipsi_energy_pt2(E_PT2)
 !     call ezfio_get_casscf_cipsi_energy(PT2)
+     double precision :: delta_E_istate, e_av
+     e_av = 0.d0
      do istate=1,N_states
-     call write_double(6,E_PT2(istate),'E + PT2 energy = ')
-     call write_double(6,PT2(istate),'  PT2          = ')
+      e_av += state_average_weight(istate) * Ev(istate) 
+      if(istate.gt.1)then
+       delta_E_istate = E_PT2(istate)  - E_PT2(1)
+      write(*,'(A6,I2,A18,F16.10)')'state ',istate,' Delta E+PT2    = ',delta_E_istate
+      endif
+      write(*,'(A6,I2,A18,F16.10)')'state ',istate,' E + PT2 energy = ',E_PT2(istate)
+      write(*,'(A6,I2,A18,F16.10)')'state ',istate,'     PT2 energy = ',PT2(istate)
+!      call write_double(6,E_PT2(istate),'E + PT2 energy = ')
+!      call write_double(6,PT2(istate),'  PT2          = ')
      enddo
+     call write_double(6,e_av,'State-average CAS-SCF energy bis = ')
      call write_double(6,pt2_max,' PT2_MAX       = ')
 !    endif
 

src/casscf_cipsi/example_casscf_multistate.sh

@@ -0,0 +1,66 @@
+# This is an example for MULTI STATE CALCULATION STATE AVERAGE CASSCF 
+# We will compute 3 states on the O2 molecule 
+# The Ground state and 2 degenerate excited states 
+# Please follow carefully the tuto :) 
+
+##### PREPARING THE EZFIO 
+# Set the path to your QP2 directory 
+QP_ROOT=my_fancy_path 
+source ${QP_ROOT}/quantum_package.rc 
+# Create the EZFIO folder
+qp create_ezfio -b aug-cc-pvdz O2.xyz -m 3 -a -o O2_avdz_multi_state
+# Start with ROHF orbitals 
+qp run scf 
+# Freeze the 1s orbitals of the two oxygen
+qp set_frozen_core 
+
+##### PREPARING THE ORBITALS WITH NATURAL ORBITALS OF A CIS 
+# Tell that you want 3 states in your WF
+qp set determinants n_states 3 
+# Run a CIS wave function to start your calculation 
+qp run cis | tee ${EZFIO_FILE}.cis_3_states.out 
+# Save the STATE AVERAGE natural orbitals for having a balanced description 
+# This will also order the orbitals according to their occupation number 
+# Which makes the active space selection easyer !
+qp run save_natorb | tee ${EZFIO_FILE}.natorb_3states.out 
+
+##### PREPARING A CIS GUESS WITHIN THE ACTIVE SPACE 
+# Set an active space which has the most of important excitations 
+# and that maintains symmetry : the ACTIVE ORBITALS are from """6 to 13"""
+
+# YOU FIRST FREEZE THE VIRTUALS THAT ARE NOT IN THE ACTIVE SPACE 
+# !!!!! WE SET TO "-D" for DELETED !!!!
+qp set_mo_class -c "[1-5]" -a "[6-13]" -d "[14-46]" 
+# You create a guess of CIS type WITHIN THE ACTIVE SPACE 
+qp run cis | tee ${EZFIO_FILE}.cis_3_states_active_space.out 
+# You tell to read the WFT stored (i.e. the guess we just created) 
+qp set determinants read_wf True
+
+##### DOING THE CASSCF 
+### SETTING PROPERLY THE ACTIVE SPACE FOR CASSCF 
+# You set the active space WITH THE VIRTUAL ORBITALS !!!
+# !!!!! NOW WE SET TO "-v" for VIRTUALS  !!!!!
+qp set_mo_class -c "[1-5]" -a "[6-13]" -v "[14-46]" 
+
+# You tell that it is a small actice space so the CIPSI can take all Slater determinants 
+qp set casscf_cipsi small_active_space True 
+# You specify the output file 
+output=${EZFIO_FILE}.casscf_3states.out 
+# You run the CASSCF calculation 
+qp run casscf  | tee ${output}
+
+# Some grep in order to get some numbers useful to check convergence 
+# State average energy 
+grep "State-average CAS-SCF energy =" $output | cut -d "=" -f 2 > data_e_average
+# Delta E anticipated for State-average energy, only usefull to check convergence
+grep "Predicted energy improvement =" $output | cut -d "=" -f 2 > data_improve
+# Ground state energy
+grep "state  1 E + PT2 energy"        $output | cut -d "=" -f 2 > data_1
+# First excited state energy
+grep "state  2 E + PT2 energy"        $output | cut -d "=" -f 2 > data_2
+# First excitation energy 
+grep "state  2 Delta E+PT2"           $output | cut -d "=" -f 2 > data_delta_E2
+# Second excited state energy
+grep "state  3 E + PT2 energy"        $output | cut -d "=" -f 2  > data_3
+# Second excitation energy 
+grep "state  3 Delta E+PT2"           $output | cut -d "=" -f 2 > data_delta_E3