Investigation Of Compton Profiles Of Atoms And Molecules Based On Synchrotron Radiation

The core research content of Atomic and Molecular physics is electronicstructure of atoms and molecules.Compton profiles of atoms, molecules reveal theinformation of the electron momentum density of the ground states.The Comptonprofiles of atoms, molecules measurements can be directly on the details of atomicand molecular electronic wave function, explore the cprresponding parameters.With the development of the synchrotron radiation source, more and moreexperiments of synchrotron radiation based on thesynchrotron radiation.and theresults of experimental study are more reliable.Compton profile measurements werecarried out at the beamline BL15U1,Hard X ray microfocus beamline,of the ShanghaiSynchrotron Radiation Facility (SSRF),Third generation synchrotron radiation.Withthe he basic conditions of the experimental station, designed gas cell andscaffoldsfor Compton scattering experiments.Innovative,using two same gas cells.The Compton profiles of Hydrogen, methane,nitric oxide，acetylene and ethanemolecules have been determined at an incident photon energy of20keV.Consideringthe statistical accuracy of0.2%at pz=0is achieved, the present determined Comptonprofiles of H2,CH4,NO,C2H2and C2H6can serve as the experimental benchmark data.Furthermore, the density functional theory and HF calculation with different basis setswere used to calculate the Compton profiles of H2,CH4,NO,C2H2and C2H6.ForHydrogen, the polarization function and the diffuse function do not work forimproving the accuracy of wavefunctions of H2in the ground state,the electroncorrelation effect is very important to describe the wavefunction in the groundstate ofhydrogen.It is found that the DFT calculations with the diffuse basis sets are moreclose to the experimental results, which indicates that the electronic densitydistribution of nitric oxide is more diffuse.For methane and ethane,the presentexperimental Compton profilesare in better agreement with the theoreticalcalculations in the whole pzregion than the previous experimental results.For acetylene,the HF calculation is better agreement with the experimental one,The morework is needed to elucidate this phenomenon.