Three optimized geometries of nitromethane dimer have been obtained at the HF/6–31G* level. Dimer binding energies have been corrected for the basis set superposition error (BSSE) and the zero point energy. Computed ...Three optimized geometries of nitromethane dimer have been obtained at the HF/6–31G* level. Dimer binding energies have been corrected for the basis set superposition error (BSSE) and the zero point energy. Computed results indicate that the cyclic structure of (CH3NO2)2 is the most stable of three optimized geometries, whose corrected binding energy is 17.29 kJ·mol?1 at the MP4SDTQ/6–31G*/HF/6–31G* level. In the optimized structures of nitromethane dimer, the inter-molecular hydrogen bond has not been found; and the charge-transfer interaction between CH3NO2 subsystems is weak; and the correlation interaction energy makes a little contribution to the intermolecular interaction energy of the dimer.展开更多
A series of substituted l,4-oxathiane-3-thione derivatives were synthesized via one-pot multicomponent reactions of nitromethane,carbon disulfide and oxiranes in the presence of Et;N in water as the solvent under micr...A series of substituted l,4-oxathiane-3-thione derivatives were synthesized via one-pot multicomponent reactions of nitromethane,carbon disulfide and oxiranes in the presence of Et;N in water as the solvent under microwave irradiation.Particularly valuable features of this method include high yields of products,broad substrate scope,short reaction time and straightforward procedure.展开更多
The structural,electronic and elastic properties of solid nitromethane are investigated under pressure by performing first-principles density functional theory(DFT)calculations within the generalized gradient approxim...The structural,electronic and elastic properties of solid nitromethane are investigated under pressure by performing first-principles density functional theory(DFT)calculations within the generalized gradient approximation(GGA)and the local density approximation(LDA).The obtained ground state structure properties are found to be consistent with existing experimental and theoretical results.The pressure-induced variations of structure parameters(a,b,c and V)indicate that the solid nitromethane has an anisotropic compressibility,and the compression along the c direction is more difficult than along a and b directions.From the vibration curves of intermolecular bond length and bond angle,we find that the C—N bond is the most sensitive among these bonds under pressure,suggesting that the C—N bonds may be broken first under external loading.The influence of pressure on the electronic properties of solid NM has been studied,indicating that solid NM is an insulating compound with a large indirect band gap and tends to be a semiconductor with increasing pressure.Finally,we predict the elastic constants and their pressure dependence for the solid NM with the bulk modulus,Young’s modulus,shear modulus and the Poisson’s ratio derived.展开更多
基金Project supported by the Foundation of China Academy of Engineering Physics (No. 99050330, 20000552)
文摘Three optimized geometries of nitromethane dimer have been obtained at the HF/6–31G* level. Dimer binding energies have been corrected for the basis set superposition error (BSSE) and the zero point energy. Computed results indicate that the cyclic structure of (CH3NO2)2 is the most stable of three optimized geometries, whose corrected binding energy is 17.29 kJ·mol?1 at the MP4SDTQ/6–31G*/HF/6–31G* level. In the optimized structures of nitromethane dimer, the inter-molecular hydrogen bond has not been found; and the charge-transfer interaction between CH3NO2 subsystems is weak; and the correlation interaction energy makes a little contribution to the intermolecular interaction energy of the dimer.
文摘A series of substituted l,4-oxathiane-3-thione derivatives were synthesized via one-pot multicomponent reactions of nitromethane,carbon disulfide and oxiranes in the presence of Et;N in water as the solvent under microwave irradiation.Particularly valuable features of this method include high yields of products,broad substrate scope,short reaction time and straightforward procedure.
基金supported by the Construction Plan for Scientific Research Innovation Teams of Universities in Sichuan Province(Grant No.12TD008)the National Basic Research Program of China(Grant No.2011CB808201)the Scientific Research Fund of Sichuan Provincial Education Department(Grant No.11ZB079)
文摘The structural,electronic and elastic properties of solid nitromethane are investigated under pressure by performing first-principles density functional theory(DFT)calculations within the generalized gradient approximation(GGA)and the local density approximation(LDA).The obtained ground state structure properties are found to be consistent with existing experimental and theoretical results.The pressure-induced variations of structure parameters(a,b,c and V)indicate that the solid nitromethane has an anisotropic compressibility,and the compression along the c direction is more difficult than along a and b directions.From the vibration curves of intermolecular bond length and bond angle,we find that the C—N bond is the most sensitive among these bonds under pressure,suggesting that the C—N bonds may be broken first under external loading.The influence of pressure on the electronic properties of solid NM has been studied,indicating that solid NM is an insulating compound with a large indirect band gap and tends to be a semiconductor with increasing pressure.Finally,we predict the elastic constants and their pressure dependence for the solid NM with the bulk modulus,Young’s modulus,shear modulus and the Poisson’s ratio derived.