Mie Scattering of Materials

Hi, I am simulating optical photons traveling through a glass cuvette containing various samples (water for control, and liquid scintillator blends). I have implemented all the necessary properties, but I have a question about Mie scattering specifically. Is there a way to determine the values for MIEHG_FORWARD, MIEHG_BACKWARD, and MIEHG_FORWARD_RATIO for other materials? In the extended examples the values for water are given, but I do not know how to determine the other ones.