Spectra file dump feature

docs/source/options.rst

@@ -739,7 +739,7 @@ Default value: 0.25
 
 **TRANSITION_DIPOLES**
 
-Compute the transition dipole moments and oscillator strengths
+Compute the transition dipole moments and oscillator strengths, then generate 'spectra.dat' file containing the final results.
 
 Type: bool
 

forte/base_classes/active_space_method.cc

@@ -92,6 +92,8 @@ void ActiveSpaceMethod::set_print(PrintLevel level) { print_ = level; }
 
 void ActiveSpaceMethod::set_quiet_mode() { set_print(PrintLevel::Quiet); }
 
+std::map<std::string, std::vector<std::string>> ActiveSpaceMethod::get_spectra_results() { return spectra_results_; }
+
 DeterminantHashVec ActiveSpaceMethod::get_PQ_space() { return final_wfn_; }
 
 std::shared_ptr<psi::Matrix> ActiveSpaceMethod::get_PQ_evecs() { return evecs_; }
@@ -313,6 +315,12 @@ std::vector<double> ActiveSpaceMethod::compute_oscillator_strength_same_orbs(
         psi::outfile->Printf("\n    %6s %6s", name1.c_str(), name2.c_str());
         psi::outfile->Printf("%15.8f%15.8f%15.8f", e_diff, e_diff * pc_hartree2ev, out[i]);
 
+        // push to results to spectra_results_ vector
+        std::vector<std::string> data {name1, name2, std::to_string(energies_[root1]),
+                                       std::to_string(energies2[root2]), std::to_string(e_diff),
+                                       std::to_string(e_diff * pc_hartree2ev), std::to_string(out[i])};
+        add_spectra_results(data);
+
         // push to psi4 environment globals
         std::string name_env = "OSC. " + multi_label + " " + name1 + " -> " + name2;
         push_to_psi4_env_globals(out[i], name_env);
@@ -439,6 +447,11 @@ std::vector<std::shared_ptr<psi::Vector>> ActiveSpaceMethod::compute_transition_
     return trans_dipoles;
 }
 
+void ActiveSpaceMethod::add_spectra_results(const std::vector<std::string>& data){
+    std::string trans_label = data[0] + "->" + data[1];
+    spectra_results_.emplace(trans_label, data);
+}
+
 std::shared_ptr<ActiveSpaceMethod> make_active_space_method(
     const std::string& type, StateInfo state, size_t nroot, std::shared_ptr<SCFInfo> scf_info,
     std::shared_ptr<MOSpaceInfo> mo_space_info, std::shared_ptr<ActiveSpaceIntegrals> as_ints,

forte/base_classes/active_space_method.h

@@ -249,6 +249,9 @@ class ActiveSpaceMethod {
                                           const std::vector<std::pair<size_t, size_t>>& root_list,
                                           std::shared_ptr<ActiveSpaceMethod> method2);
 
+    /// Store spectra results of calculation
+    void add_spectra_results(const std::vector<std::string>& data);
+
     /// Dump the wave function to file
     /// @param file name
     virtual void dump_wave_function(const std::string&) {
@@ -336,6 +339,9 @@ class ActiveSpaceMethod {
     /// Quiet mode (no printing, for use with CASSCF)
     void set_quiet_mode();
 
+    // Get map of state_i->state_f and the spectroscopic results
+    std::map<std::string, std::vector<std::string>> get_spectra_results();
+
     /// Get the model space
     DeterminantHashVec get_PQ_space();
 
@@ -394,6 +400,9 @@ class ActiveSpaceMethod {
     /// The average value of S^2 of all the states. If empty this quantity will not be checked
     std::vector<double> spin2_;
 
+    /// Map of state_i->state_f and the spectroscopic results
+    std::map<std::string, std::vector<std::string>> spectra_results_;
+
     /// Read wave function from disk as initial guess?
     bool read_wfn_guess_ = false;
     /// Dump transition density matrix to disk?

forte/base_classes/active_space_solver.cc

@@ -29,6 +29,8 @@
 #include <algorithm>
 #include <numeric>
 #include <tuple>
+#include <fstream>
+#include <filesystem>
 
 #include "ambit/blocked_tensor.h"
 #include "ambit/tensor.h"
@@ -166,6 +168,7 @@ const std::map<StateInfo, std::vector<double>>& ActiveSpaceSolver::compute_energ
         compute_quadrupole_moment(as_mp_ints_);
         if (options_->get_bool("TRANSITION_DIPOLES")) {
             compute_fosc_same_orbs(as_mp_ints_);
+            dump_spectra_results();
         }
     }
 
@@ -365,6 +368,36 @@ void ActiveSpaceSolver::generalized_sigma(const StateInfo& state, std::shared_pt
     state_method_map_[state]->generalized_sigma(x, sigma);
 }
 
+void ActiveSpaceSolver::dump_spectra_results() {
+    std::filesystem::path currentPath = std::filesystem::current_path();
+    std::string filename = (currentPath / "spectra.dat").string();
+    std::ofstream outFile(filename);
+
+    if (!outFile.is_open()) {
+        std::cerr << "Error: Unable to open spectra.dat file." << std::endl;
+        return;
+    }
+
+    outFile << "State1, State2, E1, E2, E2_minus_E1, E2_minus_E1_eV, Osc_au" << std::endl;
+
+    for (const auto& m : state_method_map_) {
+        auto calculation = m.second;
+        auto spectra = calculation->get_spectra_results();
+        std::string out;
+
+        for (const auto& s : spectra) {
+            out += s.first + ", ";
+            out += std::accumulate(s.second.begin(), s.second.end(), std::string{}, 
+                                [](const std::string& a, const std::string& b) {
+                                    return a + (a.empty() ? "" : ", ") + b;
+                                    });
+            out += '\n';
+        }
+        outFile << out;
+    }
+    outFile.close();
+}
+
 void ActiveSpaceSolver::print_options() {
     print_h2("Summary of Active Space Solver Input");
 

forte/base_classes/active_space_solver.h

@@ -180,6 +180,9 @@ class ActiveSpaceSolver {
     /// Return the map of StateInfo to the wave function file name
     std::map<StateInfo, std::string> state_filename_map() const { return state_filename_map_; }
 
+    /// Save spectra data to spectra.dat file
+    void dump_spectra_results();
+
     /// Save the wave function to disk
     void dump_wave_function();
 

forte/register_forte_options.py

@@ -299,7 +299,7 @@ def register_active_space_solver_options(options):
 
     options.add_bool("READ_ACTIVE_WFN_GUESS", False, "Read CI wave function of ActiveSpaceSolver from disk")
 
-    options.add_bool("TRANSITION_DIPOLES", False, "Compute the transition dipole moments and oscillator strengths")
+    options.add_bool("TRANSITION_DIPOLES", False, "Compute the transition dipole moments and oscillator strengths, then generate 'spectra.dat' file containing the final results.")
 
     options.add_bool(
         "PRINT_DIFFERENT_GAS_ONLY",