  Radiation detection is vital for space, medical imaging, homeland security,
and environmental monitoring applications. In the past, the Monte Carlo
radiation transport toolkit, Geant4, has been employed to enable the effective
development of emerging technologies in these fields. Radiation detectors
utilising scintillator crystals have benefited from Geant4; however, Geant4
optical physics parameters for scintillator crystal modelling are sparse. This
work outlines scintillator properties for GAGG:Ce, CLLBC:Ce, BGO, NaI:Tl, and
CsI:Tl. These properties were implemented in a detailed SiPM-based
single-volume scintillation detector simulation platform developed in this
work. It was validated by its comparison to experimental measurements. For all
five scintillation materials, the platform successfully predicted the spectral
features for selected gamma ray emitting isotopes with energies between 30 keV
to 2 MeV. The full width half maximum (FWHM) and normalised cross-correlation
coefficient (NCCC) between simulated and experimental energy spectra were also
compared. The majority of simulated FWHM values reproduced the experimental
results within a 2% difference, and the majority of NCCC values demonstrated
agreement between the simulated and experimental energy spectra. Discrepancies
in these figures of merit were attributed to detector signal processing
electronics modelling and geometry approximations within the detector and
surrounding experimental environment.
