Potential energy surfaces(PESs), vibrational frequencies, and infrared spectra are calculated for NF_(3)^(+) using ab initio calculations, based on UCCSD(T)/cc-p VTZ combined with vibrational configuration interaction...Potential energy surfaces(PESs), vibrational frequencies, and infrared spectra are calculated for NF_(3)^(+) using ab initio calculations, based on UCCSD(T)/cc-p VTZ combined with vibrational configuration interaction(VCI). Based on an iterative algorithm, the surfaces(SURF) program adds automatic points to the lattice representation of the potential function, the one-dimensional and two-dimensional PESs are calculated after reaching a convergence threshold, finally the smooth image of the potential energy surface is fitted. The PESs accurately account for the interaction between the different modes, with the mode q_(6) symmetrical stretching vibrations having the greatest effect on the potential energy change of the whole system throughout the potential energy surface shift. The anharmonic frequencies are obtained when the VCI matrix is diagonalized. Fundamental frequencies, overtones, and combination bands of NF_(3)^(+) are calculated, which generate the degenerate phenomenon between their frequencies. Finally, the calculated anharmonic frequency is used to plot the infrared spectra.Modal antisymmetric stretching ν_(5) and symmetric stretching ν_(6) exhibit a phenomenon of large-intensity borrowing. This study can provide data to support the characterization in the laboratory.展开更多
Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-v...Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-visible(UV-vis)spectroscopy are used to characterize its morphological and optical properties,and its growth mechanism is discussed.The key factors for the formation of flower-like WS_(2)are determined.Firstly,the cooling process causes the generation of nucleation dislocations,and then the"leaf"growth of flower-like WS_(2)is achieved by increasing the temperature.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.52002318 and 22103061)。
文摘Potential energy surfaces(PESs), vibrational frequencies, and infrared spectra are calculated for NF_(3)^(+) using ab initio calculations, based on UCCSD(T)/cc-p VTZ combined with vibrational configuration interaction(VCI). Based on an iterative algorithm, the surfaces(SURF) program adds automatic points to the lattice representation of the potential function, the one-dimensional and two-dimensional PESs are calculated after reaching a convergence threshold, finally the smooth image of the potential energy surface is fitted. The PESs accurately account for the interaction between the different modes, with the mode q_(6) symmetrical stretching vibrations having the greatest effect on the potential energy change of the whole system throughout the potential energy surface shift. The anharmonic frequencies are obtained when the VCI matrix is diagonalized. Fundamental frequencies, overtones, and combination bands of NF_(3)^(+) are calculated, which generate the degenerate phenomenon between their frequencies. Finally, the calculated anharmonic frequency is used to plot the infrared spectra.Modal antisymmetric stretching ν_(5) and symmetric stretching ν_(6) exhibit a phenomenon of large-intensity borrowing. This study can provide data to support the characterization in the laboratory.
基金Project supported by the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(Grant No.2020GXLH-Z-029)。
文摘Flower-like tungsten disulfide(WS_(2))with a diameter of 5-10μm is prepared by chemical vapor deposition(CVD).Scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),Raman spectroscopy,and ultraviolet-visible(UV-vis)spectroscopy are used to characterize its morphological and optical properties,and its growth mechanism is discussed.The key factors for the formation of flower-like WS_(2)are determined.Firstly,the cooling process causes the generation of nucleation dislocations,and then the"leaf"growth of flower-like WS_(2)is achieved by increasing the temperature.