Irradiation theoretical modeling

A theoretical model of the low-temperature decay of etr in MTHF discovered in ref. 30 was suggested in ref. 31. According to this model, the disappearance of et in y-irradiated MTHF at 77 K is due to electron tunneling from a trap to a hole centre. The form of the potential barrier for electron tunneling used in ref. 31 to analyze the curves of the decay of etr is represented schematically in Fig. 9(a). To evaluate the probability of tunneling per unit of time, the Gamow formula... 

The photochemical reduction of y is further rationalized by a theoretical model that neglects photo-orientation effects to EFISH and assumes that y of the chromophore decreases upon trans to cis molecular shape change. The model predicts an EFISH intensity at the photostationary state, which varies hyperbolically relative to the irradiating light intensity. Indeed, hyperbolic functions were adjusted to the experimental data showing the variation of the SH intensity at the steady state of the irradiation versus the irradiation intensity for both PI-1 and PI-2 (not shown). This finding demonstrates that the azo chromophores in PI-1 and PI-2 behave consistently with the model, and validates the concept of the reversible rapid photochemical erase of y oi these isomerizable NLO dyes. 

Eckman, R.S., The response of ozone to short-term variations in the solar ultraviolet irradiance, 1. A theoretical model. J Geophys Res 91, 6695, 1986. 

An important contribution to the theoretical model formation originates from the use of vacuum-ultraviolet radiation from a synchrotron source [6). It was shown that photostimulable centers in BaFBr Fu can be created by irradiation into the vacuum-ultraviolet region (> 6.7 eV), i.e. in the excitonic and interband region of the host lattice. 

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