The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. ...The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.展开更多
Molecular dynamics （MD） computer simulations have been carried out to study the structures, properties and crystal nucleation of nanoparticles with 453 Cu atoms. Structure information was analyzed from the MD simula...Molecular dynamics （MD） computer simulations have been carried out to study the structures, properties and crystal nucleation of nanoparticles with 453 Cu atoms. Structure information was analyzed from the MD simulations, while properties of nanoparticles of Cu453, such as melting point, freezing temperature, heat capacity and mo- lar volumes, have been estimated. The face center cubic （FCC） phase and icosahedron （Ih） phase were observed during the quenching process, and nucleation rates of crystallization to FCC crystal of Cu453 at temperatures of 650, 700, 750, and 800 K were analyzed. Both classical nucleation theory （CNT） and diffuse interface theory （DIT） were used to interpret our observed nucleation rates. The free energy and diffuse interface thickness between the liquid and the FCC crystal phases were estimated by the CNT and DIT respectively, and the results show that the DIT does not work properly to the system.展开更多
文摘The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.
文摘Molecular dynamics （MD） computer simulations have been carried out to study the structures, properties and crystal nucleation of nanoparticles with 453 Cu atoms. Structure information was analyzed from the MD simulations, while properties of nanoparticles of Cu453, such as melting point, freezing temperature, heat capacity and mo- lar volumes, have been estimated. The face center cubic （FCC） phase and icosahedron （Ih） phase were observed during the quenching process, and nucleation rates of crystallization to FCC crystal of Cu453 at temperatures of 650, 700, 750, and 800 K were analyzed. Both classical nucleation theory （CNT） and diffuse interface theory （DIT） were used to interpret our observed nucleation rates. The free energy and diffuse interface thickness between the liquid and the FCC crystal phases were estimated by the CNT and DIT respectively, and the results show that the DIT does not work properly to the system.
