The prediction and assessment of properties for high energy density fuel – Adamantane derivatives: The combined DFT and molecular dynamics simulation

Abstract

The structures of high-energy–density fuel are significant factors to influence property, which in turn determines the flight distance and payload of vehicles. The density functional theory and molecular dynamics simulation are employed to predict properties of adamantane derivatives, and explore the effect of structure with the different substitutes and the isomers on properties including density, net heat value, specific impulse, thermal and oxidation stability. For adamantane derivatives with different substitutes, the C/H ratio is treated as the descriptors of density and net heating value. While the number of secondary carbon atom attached by side chains and the gap between HOMO and LUMO are viewed as the descriptors of density and volumetric net heating value for isomers, respectively. Based on the above descriptor, the structures with superior properties are obtained for ethyladamantane, propyladamantane and butyladamantane. The structure of pentyladamantane with excellent properties (2c-ethyl-2t,4c,4t-trimethyladamantane) is predicted due to resembling structure of adamantane derivatives with preferable properties. The thermal and oxidation stability of 2c,2t-dimethyladamantane, 2c-ethyl-2t-methyladamantane, 2c,2t-diethyladamantane and 2c-ethyl-2t,4c,4t-trimethyladamantane with superior properties is close to tetrahydro-dicyclopentadiene meeting requirement of aircraft. Therefore, the guidance, that predicts, screens and assesses the structure and property of adamantane derivatives, is provided in this study by defining descriptors.