Investigation of orbital momentum profiles of methylpropane (isobutane) by binary (e,2e) spectroscopy

Abstract

Momentum profiles of the valence orbitals of methylpropane, also known as isobutane (CH3CH(CH3)CH3), have been studied by using a high resolution binary (e,2e) electron momentum spectrometer (EMS), at an impact energy of 1200 eV plus the binding energy, and using symmetric noncoplanar kinematics. The coincidence energy resolution of the EMS spectrometer is 0.95 eV full width at half-maximum. The experimental momentum profiles of the valence orbitals are compared with the theoretical momentum distributions calculated using Hartree–Fock (HF) and density functional theory (DFT) methods with the two basis sets of 6-31G and 6-311++G**. The B3LYP functionals are used for the DFT calculations. In general, the experimental momentum distributions are well described by the HF and DFT calculations. The pole strengths of the main ionization peaks from the orbitals in the inner valence are estimated.

An investigation of valence shell orbital momentum profiles of difluoromethane by binary (e,2e) spectroscopy

“…31 Therefore only a brief description is given in this paper. 31 Therefore only a brief description is given in this paper.…”

Investigation of valence orbitals of propene by electron momentum spectroscopy

“…14 The basic principle of EMS is ionization reaction initiated by electron collision, i.e., the ͑e ,2e͒ reaction. 14 The basic principle of EMS is ionization reaction initiated by electron collision, i.e., the ͑e ,2e͒ reaction.…”

Fuelling the search for light dark matter-electron scattering with spherical proportional counters

“…Finally, we also find good agreement between our spherically-averaged methane and isobutane momentum-space wave functions and the various calculations presented in Refs. [97] and [98].…”