The photoelectron spectroscopy (PES) of iso-propyl nitrite (CH3) 2CHONO and tert -butyl nitrite (CH3)3CONO are reported. By combining the PES measurements with theoretical calculation on the compounds, we conclude that the first vertical ionization potential for the two compounds are 10.37 and 10.12 eV, respectively. An unmistakable substituent effect on the ionization potential was observed. Comparison of different calculations shows that the outer valence Green's function (OVGF) method gives quite good results in ionization potentials calculations. It is also pointed out that alkyl nitrites are good source for obtaining RO^. radicals based on the experimental and theoretical analysis.

Key words: NITROSO GROUPS, ALKANE P, AB INITIO CALCULATION, ELECTRONIC STRUCTURE, SELF-CONSISTENT FIELD