Structure-property correlations of bis(nitrofurazano) furazan(BNFF-1): A density functional theory study

This study presents structural, elastic and electronic properties of BNFF-1 using density functional theory (DFT). For obtaining correct ground state structure, two different dispersion corrected methods (Grimme (G06) and Tkatchenko-Scheffler (TS)) along with standard DFT functional have been used. The obtained results with TS functional show less deviation (∼1.2%) than G06 (∼1.7%). This small difference could be due to the relative variation in dispersion coefficients incorporated. The structural parameters from van der Waals (vdW) corrected schemes clearly informs about the role of weak interactions and bond polarizability differences on the structural stability of BNFF-1. The calculated bulk modulus and its pressure derivative using third order birch murnaghan equation of state are 11.43 GPa (17.46 GPa: polycrystalline using Hill approximation) and 8.17 respectively. From the magnitude of bulk modulus we can conclude that BNFF-1 is similar to well known energetic material RDX. The order of compressibility of the lattice parameters obtained from the first order pressure coefficient is c > a > b. The study of elastic constants and the related properties of this material has also been carried out to know the impact and frictional sensitivity of this material. At the end, electronic band structure calculation results at TS level, reveal that, BNFF-1 is a direct band gap (3.02 eV) material along Γ-Γ direction in the first Brillion zone. Overall, the effect of bond polarizability through TS-scheme is well addressed in order to understand the various structure-property correlations.