Calculating Excited Electronic States using MRCC

You should specify the reference determinant in the MINP file, e.g.:

refdet=vector
2 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

If you want to run an MRCCSDT calculation, you should also define the active space using active keyword.

1- If we have 2 atoms (diatomic molecule) in the present work, how can we present the input records of the vector of each atom? Shall we put each atom on a new line? Which atom shall we start with?

2- Is the ECP included in the refdet=vector?

3- If we have a doubly occupied orbital and it is active, shall we consider it 2 or 1?

Thank you very much for your continuous help and support...

Please read the description of keyword refdet in the manual.

1. You have as many integers in the line following refdet=vector as the number of correlated orbitals, the number of atoms is irrelevant. See my previous comment.

2. ECPs are not included, only the correlated orbitals.

3. 2 is required for doubly occupied orbitals, 1 for singly occupied ones.

Sure Professor! I have read all the keywords required to be written in the MINP file. The following is the last version of the MINP file:

iface=molpro
nstates=3
calc=CCSDT
active=vector
0 1 0 0 0 1 1 0 0 0 0 1 1 1 1
refdet=vector
2 1 2 2 2 1 1 2 2 2 2 1 1 0 0
mem=20000000000

Unfortunately, the program is still giving the same results as the ground state after execution it!! Is there anything still missing?!

As far as I understand you have 5 correlated electrons. Then the definition of the reference determinant, that is, the line after refdet=vector is not correct since the sum of the integers in that line should be equal to 5.

Yes, 5 correlated electrons are considered in the calculations. I am studying the NaYb molecule by taking the ECP60MDF for the Yb-atom and a basis set for the Na atom with all electron scheme (All 11 electrons are considered). The CAS is:
occ,12,5,5,1;
core,4,2,2,0;
wf,21,1,1;

So, I changed the following in the MINP file:
active=vector
0 1 0 0 0 1 1 1 1 0 0 0 0 111111111 1

refdet=vector
2 2 2 2 2 1 0 2 2 2 2 2 0 0 0