Shu-sen Chen

Theoretical insights into the structures and mechanical properties of HMX/NQ cocrystal explosives and their complexes, and the influence of molecular ratios on their bonding energies.

AbstractMolecular dynamics (MD) methods were employed to study the binding energies and mechanical properties of selected crystal planes of 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX)/nitroguanidine (NQ) cocrystals at different molecular molar ratios. The densities and detonation velocities of the cocrystals at different molar ratios were estimated. The intermolecular interaction and bond dissociation energy (BDE) of the N–NO2 bond in the HMX:NQ (1:1) complex were calculated using the B3LYP, MP2(full) and M06-2X methods with the 6-311++G(d,p) and 6-311++G(2df,2p) basis sets. The results indicated that the HMX/NQ cocrystal prefers cocrystalizing in a 1:1 molar ratio, and the cocrystallization is dominated by the (0 2 0) and (1 0 0) facets. The K, G, and E values of the ratio of 1:1 are smaller than those of the other ratios, and the 1:1 cocrystal has the best ductility. The N–NO2 bond becomes stronger upon the formation of the intermolecular H-bonding interaction and the sensitivity of HMX decreases in the cocrystal. This sensitivity change in the HMX/NQ cocrystal originates not only from the formation of the intermolecular interaction but also from the increment of the BDE of N–NO2 bond in comparison with isolated HMX. The HMX/NQ (1:1) cocrystal exhibits good detonation performance. Reduced density gradient (RDG) reveals the nature of cocrystallization. Analysis of the surface electrostatic potential further confirmed that the sensitivity decreases in complex (or cocrystal) in comparison with that in isolated HMX.n Graphical AbstractBinding energies and mechanical properties of HMX/NQ cocrystals in different molecular molar ratios were studied using molecular dynamics methods. The origin of the sensitivity change in the HMX/NQ cocrystal originates from formation of intermolecular interactions and the bond dissociation energy increment of the N–NO2 bond

A UB3LYP and UMP2 theoretical investigation on unusual cation–π interaction between the triplet state HB=BH ( {}^3\Sigma_g^{-} ) and H+, Li+, Na+, Be2+ or Mg2+

AbstractThe nature of the unusual cation–π interactions between cations (H+, Li+, Na+, Be2+ and Mg2+) and the electron-deficient B=B bond of the triplet state HB=BH (

Can BB triple bond be as potential proton acceptor: An ab initio study on unusual intermolecular T-shaped X–H···π interactions between OCBBCO and HF, HCl, HCN or H2C2

{}^3Sigma_g^{-}

Can the BB multiple bonds be as the stronger hydrogen-bond proton acceptors than the CC multiple bonds: A comparative theoretical investigation on unusual intermolecular T-shaped XH…π interaction between HF and HBBH (3Σg-), HBBH (1Δg), OCBBCO, H2CCH2 or HCCH

) was investigated using UMP2(full) and UB3LYP methods at 6–311++G(2df,2p) and aug-cc-pVTZ levels, accompanied by a comparison with 1:1 and 2:1 σ-binding complexes between BH and the cations. The binding energies follow the order HB=BH...H+xa0>xa0HB=BH...Be2+xa0>xa0HB=BH...Mg2+xa0≫xa0HB=BH...Li+xa0>xa0HB=BH...Na+ and HB=BH (1Δg)...M+/M2+xa0>xa0H2C=CH2...M+/M2+xa0>xa0HC≡CH...M+/M2+xa0>xa0HB=BH (

Unusual intermolecular T-shaped X–H…π interactions between CH3CN/CH3NC and H2O, NH3 or C2H2: A B3LYP and MP2 theoretical study

{}^3Sigma_g^{-}

Erratum to: A UB3LYP and UMP2 theoretical investigation on unusual cation-π interaction between the triplet state HB=BH \( \left( {^3\sum {_{\text{g}}^{-} } } \right) \) and H + , Li + , Na + , Be 2+ or Mg 2+

)...M+/M2+. Furthermore, except for HB...H+, the σ-binding interaction energy of the 1:1 complex HB...M+/M2+ is stronger than the cation–π interaction energy of the C2H2...M+/M2+, C2H4...M+/M2+, B2H2 (1Δg)...M+/M2+ or B2H2 (