Performance Prediction Of Energetic Compounds And Molecular Design Research Of Several Novel Compounds

The basic performance parameters of energetic compounds are significant indicators for evaluating their energy levels and safety performances,and are basis for determining their practical applications.Customizing specific compound through molecular design and using appropriate theoretical methods to predict its energy levels and safety properties are of guiding significance to promote experimental researches of these specific compound.In this article,the energy performances calculation program has been compiled based on principles of thermochemistry and conservation equations of mass and energy.By using quantum chemistry research methods,theoretical calculations have been conducted to study the densities,enthalpies of formation,energy parameters,safety performances,and intramolecular weak interactions of nitroform salts and pyrazine derivatives containing fluorine.The main contents are as follows:(1)Based on the minimun Gibbs free energy method and conservation equations of mass and energy,a thermochemical program is compiled by FORTRAN to calculate the energy characteristics and the burning products'equilibrium ingredients of energetic compounds at a given pressure.For nitro and nitramine energetic compounds,the average absolute error of this program is within 5%.The visualization software EC,which is built by MFC and internally installed the thermochemical program and Kamlet-Jacobs equations,can quickly predict the energy performances of compounds.(2)Four nitroform ionic salts are design based on the strategy that nitroform is selected as anion and hydrazine,ammonium,guanidine,aminotriazole,aminotetrazole are selected as cations.Theoretical density and soild phase enthalpies of formation are studied at M062X-D3/ma-def2TZVP//M062X-D3/def2SVP basis set and the energy performances was estimated by EC software.The combination between anion and cation is studied by SAPT/JUN-CC-PVTZ and M062X-D3/JUN-CC-PVTZ methods.The weak interaction between anion and cation is analyzed through AIM and RDG methods.The results show that there exsit multiple N-H…O weak hydrogen bonds and van der Walls repulsion between anion and cation.The combination of anion and cation is mainly depend on the electrostatic interaction.The bingding energy of salts is in the range of 390-430 kJ/mol,indicating that these salts have good stability.Densities,detonation velocities of all salts are above 1.81g/cm~3 and 8.6 km/s.The theoretical specific impulses of all salts are within 2200-2700 N·s/kg.High energy density salts are selected from the five salts based on anticipatory targets and crystal forms of selected ones are predicted.(3)An advanced molecular design concept is adopted to design ten fluorine-containing pyrazine compounds:Replace nitro groups whith fluorine-containing groups while remaining amino groups and choose the suitable substitution positions to make intramolecular hydrogen bonds between hydrogen atoms from the amino or pyrazine ring and fluorine or oxygen atoms as much as possible.Theoretical studies on its energy levels,thermal stabilities and impact sensitivities indicate that the increase in fluorine content can effectively increase density but obviously reduce enthalpy of formation.There exist N-H…O,N-H…F and N-H…N hydrogen bonds in all compounds molecules.For compounds with the same energetic group,the more hydrogen bonds the molecule has,the greater the characteristic drop height is.The weakest bond dissociation energies of all compounds are all greater than 120 kJ/mol,which have meeting the thermal stability requirements of high-quality energetic compounds.Two high detonation heats and insensitive compounds containing fluorine are screened out according to anticipated targets.