Aby kod był przejrzysty definicja własności materiałowych powinna mieć miejsce w funkcji
  MyDetectorConstruction::DefineMaterials()

W pliku      src/MyDetectorConstruction.cc    (zmiany kolorem czerwonym)

.......................................................................................................................
void MyDetectorConstruction::DefineMaterials()
{
----------------------------------------------------------------------------------------------
 
  // Dump material information
  G4cout << *(G4Material::GetMaterialTable()) << G4endl;

  const G4int NUMENTRIES = 9;

  G4double Scnt_PP[NUMENTRIES] = { 6.6*eV, 6.7*eV, 6.8*eV, 6.9*eV, 7.0*eV, 7.1*eV, 7.2*eV, 7.3*eV, 7.4*eV };
  G4double Scnt_FAST[NUMENTRIES] = { 0.000134, 0.004432, 0.053991, 0.241971, 0.398942, 0.000134, 0.004432, 0.053991, 0.241971 };
  G4double Scnt_SLOW[NUMENTRIES] = { 0.000010, 0.000020, 0.000030, 0.004000, 0.008000, 0.005000, 0.020000, 0.001000, 0.000010 };

 G4MaterialPropertiesTable* Scnt_MPT = new G4MaterialPropertiesTable();
 Scnt_MPT->AddProperty("FASTCOMPONENT", Scnt_PP, Scnt_FAST, NUMENTRIES);
 Scnt_MPT->AddProperty("SLOWCOMPONENT", Scnt_PP, Scnt_SLOW, NUMENTRIES);
 Scnt_MPT->AddConstProperty("SCINTILLATIONYIELD", 5000./MeV);
 Scnt_MPT->AddConstProperty("RESOLUTIONSCALE", 2.0);
 Scnt_MPT->AddConstProperty("FASTTIMECONSTANT", 1.*ns);
 Scnt_MPT->AddConstProperty("SLOWTIMECONSTANT", 10.*ns);
 Scnt_MPT->AddConstProperty("YIELDRATIO", 0.8);

 PbWO4->SetMaterialPropertiesTable(Scnt_MPT);
 PbWO4->GetMaterialPropertiesTable()->DumpTable();
}