Optical Properties of beta-RDX Thin Films Deposited on Gold and Stainless Steel Substrates Calculated from Reflection-Absorption Infrared Spectra

摘要

The optical properties for crystalline films of the highly energetic material (HEM) hexahydro-1,3,5-trinitro-s-triazine, which is also known as RDX, deposited on gold (Au) and stainless steel (SS) substrates are presented. RDX has two important stable conformational polymorphs at room temperature: -RDX and -RDX. The optical properties obtained in the present work correspond to thin film samples of predominantly -RDX polymorph. The infrared spectroscopic intensities measured showed significant differences in the -RDX crystalline films deposited on the two substrates with respect to the calculated real part of refractive index. The -RDX/Au crystalline films have a high dynamic response, which is characterized by the asymmetric stretching mode of the axial nitro groups, whereas for the -RDX/SS crystalline films, the dynamic response was mediated by the -N-NO2 symmetric stretch mode. This result provides an idea of how the electric field vector propagates through the -RDX crystalline films deposited on the two substrates.