Electron exchange between dopant iron sites in glass films of arsenic selenide

Electronic exchange between centres of iron in the vitreous arsenic selenide

“…10), and the relative area under the spectrum corresponding to Fe 2+ sites is decreased (Fig. 11) (Marchenko, Luzhkov, Rasnyuk et al 2017). for an iron concentration of (1) 2 and (2) 4 at.%, and (3) of Fe 2+ sites for an iron concentration of 4 at.%; the dashed lines correspond to the temperature dependences of the central shifts of the Mössbauer spectra of the (I) Fe 3+ and (II) Fe 2+ sites, which are determined from the temperature dependences of the squared Doppler shifts in the 57 Fe Mössbauer spectra Fig.…”

“…It is obvious that when the Fermi level is close to the level of iron, the electron exchange between the two oxidation states of iron (Fe 2+ and Fe 3+ ) is possible, which should give rise to the convergence of the central shift values of the Mössbauer spectra of the Fe 2+ and Fe3+ sites. In the limit of fast electron exchange, when the lifetimes of the Fe 2+ and Fe 3+ states are much shorter than the lifetime of the 57 mFe nuclear isomer (~10 -7 s), the Mössbauer spectrum of the averaged state of iron with the following central shift should be (Marchenko, Luzhkov, Rasnyuk et al 2017):…”

“…The temperature dependences of the central shifts of the Mössbauer spectra of Fe 3+ and Fe 2+ sites at NFe = 2 at.% (when Р ≈ 0) and NFe = 4 at.% (when Р ≈ 1) are shown in Fig. 8 (Marchenko, Luzhkov, Rasnyuk et al 2017) DOI: 10.33910/2687-153X-2020-1-2-61-69…”

“…is the Debye function, and ΔT is the difference between the temperatures at which the Mössbauer spectra of the sample are recorded (Marchenko, Luzhkov, Rasnyuk et al 2017).…”

“…In particular, the electrical activity of iron impurity atoms was discovered in glassy films of arsenic selenide back in 1990 (Turaev, Seregin, Nasredinov 1990). Later, we undertook studies of both the nature of the electrical activity of iron (Marchenko, Luzhkov, Rasnyuk et al 2017;Marchenko, Terukov, Egorova et al 2017) and the mechanism of electrical activity of the different states of iron in As 2 Se 3 (Bobokhuzhaev, Rabchanova, Seregin, Shaldenkova 2015;Marchenko, Rabchanova, Seregin et al 2016). In this paper, we consider all the results we obtained (Bobokhuzhaev, Rabchanova, Seregin, Shaldenkova 2015;Marchenko, Rabchanova, Seregin et al 2016;Marchenko, Luzhkov, Rasnyuk et al 2017, Marchenko, Terukov, Egorova et al 2017Marchenko, Nasredinov, Seregin 2018;Turaev, Seregin, Nasredinov 1990) from a single perspective.…”