关键词: 甲烷分子, 价轨道, 电子动量谱学, 基函数

Abstract:

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 It_2 and 2a_1 valence orbitals of methane are measured. Excellent agreement can be found between the experimental data and the calculations using the Hartree-Fock method and CI method with the 146-GTO basis functions. In the inner valence region clearly satellite structures of the 2a1 orbita1 are observed. The experimental binding energies and pole strengths are compared with the result, of 2ph-TDA Green function's calculation. EMS measurements and the 2ph-IDA calculation can give The consistent values of binding energies, while the 2ph-TDA calculation is found to overestimate the maim peak intensity of 2a1 orbital and underestimate the intensity of satallite structures.

Key words: Methane, Valence orbital, Electron momentum spectroscopy, Basis function