Record Species in different Volume & copynum

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Geant4 Version: 11.2.beta
_Operating System:_Windows
CMake Version:

Hello, everyone
Recently, I am working to record different species in the multiple cells, I have added ScoreSpecies into MutiFunctionalDetector as SensitiveDetector in multiple mode. In the RunAction, I find that I can’t distinguish the molecular from different cells.I have add some output in TimeStepAction, but it’s not what I need. Now I want to add some functions in G4MoleculeCounter as following, but I can’t find the program’s interface.

void TimeStepAction::UserReactionAction(const G4Track& a, const G4Track& b,
                                        const std::vector<G4Track*>* products)
    G4double time = a.GetGlobalTime();
    auto LogicalVolume = a.GetLogicalVolumeAtVertex();
    G4String Name = LogicalVolume->GetName();
    G4int copynum = a.GetTouchable()->GetCopyNumber();
    G4cout << "current_time :  " << time << " current Volume name : " << Name 
        << " The copynum : "<< copynum <<G4endl;}

I appreciate any help you can provide. :smile:

Dear experts,
I find the program’s interface in the, Function G4Track* G4Molecule::BuildTrack

G4Track* G4Molecule::BuildTrack(G4double globalTime,
                                 const G4ThreeVector& position)
    if (fpTrack != nullptr)
        G4Exception("G4Molecule::BuildTrack", "Molecule001", FatalErrorInArgument,
                    "A track was already assigned to this molecule");

    // Kinetic Values
    // Set a random direction to the molecule
    G4double costheta = (2 * G4UniformRand() - 1);
    G4double theta = acos(costheta);
    G4double phi = 2 * pi * G4UniformRand();

    G4double xMomentum = cos(phi) * sin(theta);
    G4double yMomentum = sin(theta) * sin(phi);
    G4double zMomentum = costheta;

    G4ThreeVector MomentumDirection(xMomentum, yMomentum, zMomentum);
    G4double KineticEnergy = GetKineticEnergy();

    G4DynamicParticle* dynamicParticle = new G4DynamicParticle(
        fpMolecularConfiguration->GetDefinition(), MomentumDirection,

    G4cout << "Here is BuildTrack() " ;

    //Set the Track
    fpTrack = new G4Track(dynamicParticle, globalTime, position);

    G4String Volume_name = fpTrack->GetLogicalVolumeAtVertex()->GetName();
    G4String Copynum = std::to_string(fpTrack->GetTouchable()->GetCopyNumber());
    G4String AreaName = Volume_name + Copynum;
    if (G4VMoleculeCounter::Instance()->InUse())
    G4cout << " AreaName is : "<< AreaName << G4endl;
    return fpTrack;

It can be compiled successfully, but there is always an error when running the corresponding process.dll. I want to know if there is a way to return the Volume where the particle is located to the MoleculeCounter at the beginning of particle creation?