It is important to predict the intensity distribution in focusing plane for designing the X-ray compound refractive lenses. On the basis of analyzing the structure of X-ray compound lenses and comparing it with Praunh...It is important to predict the intensity distribution in focusing plane for designing the X-ray compound refractive lenses. On the basis of analyzing the structure of X-ray compound lenses and comparing it with Praunhofer diffraction system, it is concluded that the X-ray focusing system can be regarded as a kind of Praunhofer diffraction system. Therefore, a method based on Fourier spectrum analysis is presented to predict the intensity distribution in the focusing plane for the X-ray lenses. A brief analysis on the relationship between the parameters of X-ray lenses and their focusing performance is also given in this paper.展开更多
The ab initio calculation methods have been used to calculate the spectral and electronic characteristics of difluorocarbene in the ground electronic state(~1A_1),the lowest-lying singlet(~1B_1)and triplet(~3B_1)state...The ab initio calculation methods have been used to calculate the spectral and electronic characteristics of difluorocarbene in the ground electronic state(~1A_1),the lowest-lying singlet(~1B_1)and triplet(~3B_1)states,The optimized equilibrium geometries,rotational constants,harmonic vibrational frequencies and energy gaps,electronic charges,dipole moments of these states have been computed with different basis sets.The calculated vibrational frequency of ~3B_1 state(v_2=522 cm^(-1))and the energy separation(2.26eV)between ~3B_1 and ~1A_1 states are in good agreement with the experimental re- sults(519 cm^(-1),2.46 eV respectively).According to the calculations the previous assignment of vibrational symmetries of ~1B_1 state was corrected,and some experimentally undetermined vibrational frequencies were predicted.展开更多
基金This work was performed with the support from the National Natural Science Foundation of China (No. 10174079) the fund for the qualified researchers in Zhejiang University of Technology, P. R. China.
文摘It is important to predict the intensity distribution in focusing plane for designing the X-ray compound refractive lenses. On the basis of analyzing the structure of X-ray compound lenses and comparing it with Praunhofer diffraction system, it is concluded that the X-ray focusing system can be regarded as a kind of Praunhofer diffraction system. Therefore, a method based on Fourier spectrum analysis is presented to predict the intensity distribution in the focusing plane for the X-ray lenses. A brief analysis on the relationship between the parameters of X-ray lenses and their focusing performance is also given in this paper.
文摘The ab initio calculation methods have been used to calculate the spectral and electronic characteristics of difluorocarbene in the ground electronic state(~1A_1),the lowest-lying singlet(~1B_1)and triplet(~3B_1)states,The optimized equilibrium geometries,rotational constants,harmonic vibrational frequencies and energy gaps,electronic charges,dipole moments of these states have been computed with different basis sets.The calculated vibrational frequency of ~3B_1 state(v_2=522 cm^(-1))and the energy separation(2.26eV)between ~3B_1 and ~1A_1 states are in good agreement with the experimental re- sults(519 cm^(-1),2.46 eV respectively).According to the calculations the previous assignment of vibrational symmetries of ~1B_1 state was corrected,and some experimentally undetermined vibrational frequencies were predicted.
