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A procedure is described for doping PbI 2 single crystals with Fe and Ni during vapor-phase growth in a closed system in the presence of excess iodine. The rate of mass transport in the system and the doping level of the crystals are shown to be governed by the dopant content in the source material and the source temperature. The effect of Fe and Ni doping on the low-temperature (5 K) exciton photoluminescence spectrum of PbI 2 is discussed.

For an express reveal of defects of different nature in single crystals of PbI2 a method highly sensitive to structure changes, based on the measure of low‐temperature (T = 4.5 K) exciton spectra of light reflection (RS) and photoluminescence (PL), has been used. The doping of PbI2 with impurities (In, Ga, Ag, Cu, Cd, Fe, Mn, Ni) promotes preferably the creation of the 4H‐polytype in the process of growth and one‐dimensional structure disordering. The high coefficient values of the concentration shift and broadening of substitutional solid solution (SSS) of Pb1—xMnxI2 and Pb1—xCdxI2 exciton band are explained by the realization of conditions for the creation of the 4H‐PbI2‐cluster phase. In the PL spectra of some samples representing joints of 2H+4H‐polytypes, an additional D band (λ = 499.2 nm, T = 5 K) has been revealed. The D band is characterized by the coefficient of temperature shift dE/dT = —0.25 × 10—3 eV/K which is not proper to bands connected with defects.

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The biintercalation of the layered GaSe semiconductor is carried out by ferroelectric and ferromagnetic guest components. Due to the separation of guest components, the GaSe <NaNO2+FeCl3> nanohybrid has a spatial-scale hybridity, which is due to the alternation of nanoscale regions of one phase with meso- or microdimensions of another. The results of electrical conductivity studies by impedance spectroscopy indicate a 250-fold increase after biintercalation of the GaSe single crystal, due to delocalized current carriers. Confirmation of a significant change in the impurity energy spectrum after biintercalation was obtained by the method of thermally stimulated discharge—GaSe nanohybrid <NaNO2+FeCl3> is characterized by a quasi-continuous spectrum in the entire temperature range of measurements and relaxation of the heterocharge. The GaSe <NaNO2+FeCl3> nano-hybrid is characterized by a high dielectric constant while a tangent of the dielectric loss angle is less than 1 in the high- frequency region of the spectrum. That opens the prospect of its use for the manufacture of high-quality radio- frequency capacitors. Changes in the impurity energy spectrum are investigated for low temperatures in the virtual crystal model, taking into account the Fivazov dispersion law both for the conductivity band and for the two impurity bands. The appearance of an additional gap in the spectrum of impurity states is established and its shift is investigated depending on the concentration of intercalants of different nature—intercalant-acceptor type and donor.