Merge pull request #10 from qiskit-community/another_mol

Add case of using another molecule

Author: to24toro

README.md

@@ -184,6 +184,8 @@ The following command-line options are available when running `capi-demo`. These
 | --adet_comm_size <int>      | Number of nodes used to split the alpha-determinants.            | 1             |
 | --bdet_comm_size <int>      | Number of nodes used to split the beta-determinants.             | 1             |
 | --task_comm_size <int>      | MPI communicator size for task-level parallelism.                 | 1             |
+| --energy_target <float>     | Target energy for convergence (optional).                          | -326.6 (Fe4S4)         |
+| --energy_variance <float>   | Target energy variance for convergence (optional).                     | 1.0 (Fe4S4)        |
 
 
 ## Input Data
@@ -195,6 +197,13 @@ These parameters can also be obtained using `ffsim`.
 
 - The values in the `initial_occupancies_fe4s4.json` file are the eigenvalues obtained by diagonalizing the contracted one-electron density matrix from the MP2 method.
 
+## Case of Using another molecule
+To simulate a different molecule, you need to prepare the following files:
+1. An FCIDUMP file containing the molecular integrals for the target molecule.
+2. A JSON file containing the parameters for the LUCJ circuit, including the number of orbitals, number of electrons, and other relevant settings.
+3. A JSON file defining the initial orbital occupancies.
+4. Set appropriate values for `--energy_target` and `--energy_variance` based on the target molecule.
+5. Change the file paths in the main.cpp.
 
 ## Contributing
 

src/sbd_helper.hpp

@@ -90,6 +90,14 @@ SBD generate_sbd_data(int argc, char *argv[])
             sbd.task_comm_size = std::atoi(argv[i + 1]);
             i++;
         }
+        if (std::string(argv[i]) == "--energy_target") {
+            sbd.init = std::atoi(argv[i + 1]);
+            i++;
+        }
+        if (std::string(argv[i]) == "--energy_variance") {
+            sbd.init = std::atoi(argv[i + 1]);
+            i++;
+        }
     }
     return sbd;
 }