Knowledge Bank

In order to use oscillator electronic equation for crystal there is the need to introduce the factor considering the interactions in condense medium in expression of self-consistent field displacing the natural frequency of the electronic oscillation. The square limit frequency $(\omega g1)c$ can be represented by $(\omega 1)2=0.31\omega 2+0.2761\gamma 2-0.1(4\pi e2 N s/m)(f/\theta ),\omega d2=\omega o2-\omega p2/3,\omega p2=(4\pi e2 Ne /m)(f/\theta ),$ where f is the oscillator force, $\theta$ is the interaction parameter, $Ne=N s$, e,m are electronic (molecular) density, number per molecule, charge and mass, $\gamma$ is half-width of natural absorption band, $\omega d,\omega o,\omega p$ are effective, natural and plasma frequences of electronic oscillations. The effective electronic number $sf=sf/\theta$ is given by the absorption integral $f\alpha (\omega )\delta \omega \ast (2/o)(\gamma \omega d)1/2\omega p$ The theoretical formulations are in agreement with the investigated dispersion on optical constants of polar crystal solutions near the absorption edge. In going from crystal to the solution with reducting electronic density short-wave maximum of the fundamental absorption decreases and displaces in the region of a lesser wavelength and long-wave maximum, generated by electronic phonon interaction disappeares for $Ne\ast 1020cm-3$. The fundamental absorption edge of polar crystals ($\omega g$) is limiting dulute solutions of these crystals. For triglycine sulfate crystals (122 electrons) there are $sf\ast 61$. The proposed method allows to determine ($\omega g,\omega d,\omega o,\omega p,\gamma ,f/\theta$) and other parameters of polar crystals from spectral data obtained for dulute solutions of these crystals.