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Charge carrier traps energy spectra have been investigated in silicon organic polymer poly(di-n-hexylsilane) by fractional thermally stimulated luminescence in the temperature range from 5 to 200 K. The energy spectrum of traps has been found to be discrete in nature, not the quasi-continuous, as it was considered earlier. It has been established that the traps energies form two characteristic series resulting from the vibrational quanta at 373 and 259 cm -1 , respectively. It is important that these vibrational quanta coincide with the frequencies of the totally symmetric vibrational modes of silicon chain which are active in Raman spectrum. The regularities mentioned are analyzed using the oscillatory traps model as the basis.

Nanocomposite films based on an organosilicon polymer, poly(di-n-hexylsilane) (PDHS), introduced into SiO 2 film pores were prepared by a method developed herein. The dependences of optical spectra of the composites on both the polymer concentration within the porous silica films and temperature variations in the range 15-310 K have been studied. A comparison of spectra of the prepared films and PDHS/SBA-15 porous silica nanocomposites that were studied previously revealed the coexistence in the films of three spatially independent polymer photoluminescence centers corresponding to isolated polymer chains in trans-and gaucheconformations and their aggregates. The strongest band in the photoluminescence spectrum of the nanocomposite films belongs to PDHS aggregates. Its intensity exhibits an extraordinary increase as the temperature rises from 260 K to 310 K. This is supposedly associated with the additional formation of aggregates during the trans×gauche thermochromic transition.Introduction. The use of nano-sized polymers in optoelectronics, microelectronics, and medicine stimulates the study of their optical and electrical properties in order to prepare materials based on them with improved properties. A promising method for preparing nano-sized polymers is the fabrication of host-guest nanocomposites where polymers are introduced into nano-sized pores of materials based on SiO 2 . Studies of photoluminescence (PL) and PL excitation spectra and x-ray diffraction patterns of PDHS and poly(methylphenylsilane) nanocomposites introduced into MCM-41 and SBA-15 mesoporous silicas showed that the polymer was localized in the pores of the mesoporous silica [1,2]. This increased significantly the stability of the polymer [3]. These studies enabled information on the changes of optical properties on going from the isolated polymer chain to a film with the silica pore diameter varying from 2.8 to 10 nm to be obtained for the first time [1,2,4]. The changes were due to the appearance in the limited pore volume of new polymer structures with different degrees of ordering that were not observed in films and solutions of the polymers. They arose as a result of competing polymer-polymer and polymer-pore-surface intermolecular interactions. The formation of new polymer structures in the limited pore volume enabled the PL spectrum [1, 2] and PL lifetime [5] to be intentionally changed and relaxation processes and random disordering in the polymers to be influenced [6]. Thus, it was shown that the polymer properties could be controlled on the nano-scale in order to create new nanomaterials. All these studies were carried out using composites as powders. This limited significantly their further study and application.Herein a new class of mesoporous materials based on SiO 2 films with a given pore size and high specific surface area is used as the "host." The "guest" is the organosilicon polymer PDHS. This photoconductive polymer has a high PL quantum yield and significant charge-carrier mobility. These properties make it promising...