The electronic structure of methane has been studied in detail by the high Performance energy multichannel electron momentum spectrometer developed recently. The accurate electron momentum distributions of the It2 and...The electronic structure of methane has been studied in detail by the high Performance energy multichannel electron momentum spectrometer developed recently. The accurate electron momentum distributions of the It2 and 2a1 valence.orbitals of methane are measured. Excellent,agreernent can be found between the experimental data and the calculittions using the HartreeFock method and CI method with the 146-GTO basis functions. In the inner valnce regionclearly satellite structures of the 2a1 orbita1 are observed. The experimental binding energiesand pole strengths are compared with the result, of 2ph-TDA Green function’s calculation. EMSmeasurements and the 2ph-IDA calculation can give The consistent values of binding energies,while the 2ph-TDA calculation is found to overestimate the mam peak intensity of 2a1 orbit,andmderestimate the intensity of satallite structures.展开更多
We briefly present in this paper the results of 1200eV non-coplanar symmetric (e, 2e) binding energy spectrum of argon and an electron momentum profile of argon 3p.They were measured by a newly constructed spectromete...We briefly present in this paper the results of 1200eV non-coplanar symmetric (e, 2e) binding energy spectrum of argon and an electron momentum profile of argon 3p.They were measured by a newly constructed spectrometer with position-sensitive detectors in USTC. We use non-birming mode to get the Ar3p、 3s and 3s satellites binding energy spectra separately. The experAnental results is well consistent with the available theoretical results.展开更多
The electron momentum spectroscopy of the inner valence orbitals 3a 1 and 2b 2 of methylene fluoride was studied by electron momentum spectroscopy(EMS). The experiment was performed using a high resolution(ΔE=1.15 eV...The electron momentum spectroscopy of the inner valence orbitals 3a 1 and 2b 2 of methylene fluoride was studied by electron momentum spectroscopy(EMS). The experiment was performed using a high resolution(ΔE=1.15 eV FWHM, Δp=0.1 a.u.)(e,2e) EMS spectrometer. The experimental momentum profiles of these two orbitals are compared with those calculated by Hartree-Fork method and Density Functional Theory.展开更多
The electron momentum distribution of 3σ_u orbital of carbon dioxide has been measured at high momentum resolution. Through comparation between experimental and theoretical results, the calculation by DFT-B3LYP metho...The electron momentum distribution of 3σ_u orbital of carbon dioxide has been measured at high momentum resolution. Through comparation between experimental and theoretical results, the calculation by DFT-B3LYP method using 6- 311 + +G basis set is more agreement with the experirnental data than other calculations.展开更多
The binding energy spectra and momentum profiles for the valence shells of ethane have been measured by using multichannel EMS spectrometer. The results are compared with the available experimental and theoretical res...The binding energy spectra and momentum profiles for the valence shells of ethane have been measured by using multichannel EMS spectrometer. The results are compared with the available experimental and theoretical results. The present result of the experimental momentum profile of 3a1g has an obvious minimum as predicted by the theoretical calculations.展开更多
The frontier molecular orbitals （HOMO and NHOMO） of CF2BrCl molecule have been firstly investigated by （e,2e） electron momentum spectroscopy. The experimental momentum profiles are compared with the theoretical pr...The frontier molecular orbitals （HOMO and NHOMO） of CF2BrCl molecule have been firstly investigated by （e,2e） electron momentum spectroscopy. The experimental momentum profiles are compared with the theoretical profiles employing Hartree-Fock and density functional theory with 6-31G and 6-311+G（d） basis sets. Both HF and DFT calculations using 6-311+G（d） basis set can well describe the experiment, whereas those calculated using 6-31G basis set largely underestimate the experiment at the low momentum region. Furthermore, orbital electron density images show that HOMO and NHOMO have a mixed character of the bromine and chlorine lone pairs.展开更多
文摘The electronic structure of methane has been studied in detail by the high Performance energy multichannel electron momentum spectrometer developed recently. The accurate electron momentum distributions of the It2 and 2a1 valence.orbitals of methane are measured. Excellent,agreernent can be found between the experimental data and the calculittions using the HartreeFock method and CI method with the 146-GTO basis functions. In the inner valnce regionclearly satellite structures of the 2a1 orbita1 are observed. The experimental binding energiesand pole strengths are compared with the result, of 2ph-TDA Green function’s calculation. EMSmeasurements and the 2ph-IDA calculation can give The consistent values of binding energies,while the 2ph-TDA calculation is found to overestimate the mam peak intensity of 2a1 orbit,andmderestimate the intensity of satallite structures.
文摘We briefly present in this paper the results of 1200eV non-coplanar symmetric (e, 2e) binding energy spectrum of argon and an electron momentum profile of argon 3p.They were measured by a newly constructed spectrometer with position-sensitive detectors in USTC. We use non-birming mode to get the Ar3p、 3s and 3s satellites binding energy spectra separately. The experAnental results is well consistent with the available theoretical results.
文摘The electron momentum spectroscopy of the inner valence orbitals 3a 1 and 2b 2 of methylene fluoride was studied by electron momentum spectroscopy(EMS). The experiment was performed using a high resolution(ΔE=1.15 eV FWHM, Δp=0.1 a.u.)(e,2e) EMS spectrometer. The experimental momentum profiles of these two orbitals are compared with those calculated by Hartree-Fork method and Density Functional Theory.
文摘The electron momentum distribution of 3σ_u orbital of carbon dioxide has been measured at high momentum resolution. Through comparation between experimental and theoretical results, the calculation by DFT-B3LYP method using 6- 311 + +G basis set is more agreement with the experirnental data than other calculations.
文摘The binding energy spectra and momentum profiles for the valence shells of ethane have been measured by using multichannel EMS spectrometer. The results are compared with the available experimental and theoretical results. The present result of the experimental momentum profile of 3a1g has an obvious minimum as predicted by the theoretical calculations.
文摘The frontier molecular orbitals （HOMO and NHOMO） of CF2BrCl molecule have been firstly investigated by （e,2e） electron momentum spectroscopy. The experimental momentum profiles are compared with the theoretical profiles employing Hartree-Fock and density functional theory with 6-31G and 6-311+G（d） basis sets. Both HF and DFT calculations using 6-311+G（d） basis set can well describe the experiment, whereas those calculated using 6-31G basis set largely underestimate the experiment at the low momentum region. Furthermore, orbital electron density images show that HOMO and NHOMO have a mixed character of the bromine and chlorine lone pairs.
