Today I read a text in a paper, it is very helpful to ours which love chemistry.
so I catch the Abstract share with you: The photoionization mass spectroscopy (PIMS) and photoionization efficiency spectroscopy (PIES) of Kr and Kr2 have been obtained using supersonic molecule beam, synchrotron radiation and reflection time of flight mass spectrum (RTOF-MS), and the ionization energies of Kr and Kr2 were determined from their PIES. The geometries, harmonic vibrational frequencies, and ionization energies of Kr2 have also been calculated using MP2(Full)/6-31G*，QCISD/cc-pVTZ and B3LYP/6-31G. When the same level of theory is used, the structure and ionization energy are nearly unchanged, and the vibrational frequency is decreased gradually with increasing of m/z of Kr isotope. At the same time, the ionization energies of Kr (84) and Kr2 (168) were calculated using G2 theory and high accuracy energy model program. The theoretical values of the ionization energy are in agreement with those experimental ones.
