Development of various technologies (MBE, PLD - pulse laser deposition, laser surface engineering) have made it possible and necessary to study and numerically simulate effect of ambient oxygen chemisorption on operation of the active element prepared by means of the technology. This effect is seemed to be of special importance for electro-optical devices based on A2B6 bulk and thin film materials (CdTe, ZnTe, ZnSe). Native oxide may be considered as a functional part of the structure as a whole. In the abstract we report for the first time experimental data obtained from electric-field measurements performed at the room temperature and photoluminescense at 77 K on the structures A²B⁶- monocrystal/native oxide and CdTe(PLD-thin film)/native oxide present results of numerically modeled chemisorption behavior of oxygen on CdTe. The electric investigations of (ZnTe, CdTe)-monocrystal/native oxide structures have been shown Schottky-like behavior of the field characteristics. Photoluminescence studies of ZnSe-monocrystal/native oxide structures have also demonstrated some special peculiarities of the spectra to be interesting for prospective device preparation.