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The results of investigation of a variety of new organic semiconductors for optoelectronics based on thiophene and silicon by time-of-flight direct laser desorption/ionization mass spectrometry are presented. The peculiarities of the behavior of these species are analyzed. The main ionization route for many of the compounds was found to be the only formation of a molecular radical cation. For a small group of species, protonation and deprotonation were observed rather than the above path. However, there are some molecules for which several competing routes were detected, namely, the formation of a molecular radical cation, protonation, and deprotonation, Author(s): A. P. Pleshkova [sup.1], E. S. Kuznetsova [sup.2] Author Affiliations: (Aff1) 0000 0001 2192 9124, grid.4886.2, Institute of Organoelement Compounds, Russian Academy of Sciences, , 119991, Moscow, Russia (Aff2) [...]

Glass-ceramic samples of the Li1.5+xAl0.5Ge1.5SixP3–xO12 system (x = 0–0.1) were obtained by by glass crystallization. The temperatures of glass transition and of crystallization onset and peak were determined using differential scanning calorimetry. The phase composition of glass-ceramics was determined by X-ray phase analysis. Electrical conductivity was studied using electrochemical impedance. Based on the data obtained, the homogeneity region of solid solutions was established and the optimal conditions for obtaining SiO2-doped glass-ceramics were determined. The composition with x = 0.02, obtained by crystallized at 750°C at a heating rate of 3 deg/min for 2 h, had the highest lithium-ion conductivity at room temperature (4.55×10–4 S/cm). [ABSTRACT FROM AUTHOR]

ATR and transmission spectra of a series of rare-earth francisite-like phases Cu3RE(SeO3)2O2Cl (RE is a rare earth element, RE= Nd, Sm, Eu, Gd, Dy, Ho, Tm, Yb) were studied. The frequencies of the IR-active phonons of the crystals under study were determined. In the dependences of phonon frequencies on the ionic radius in a series of isostructural compounds, two tendencies are observed: a hardening of frequencies due to an increase in chemical pressure and a softening of the vibration frequencies, in which rare-earth ions are involved, due to an increase in the mass of a specific rare-earth ion. In the Cu3Dy(SeO3)2O2Cl crystal, an anomalous softening of low-frequency phonons at low temperatures was observed, which was apparently associated with the structural instability of the compound. [ABSTRACT FROM AUTHOR]

The transmission spectra of a two-dimensional frustrated magnetic Cu3Sm(SeO3)2O2Cl were measured in the region of f–f -transitions of the Sm3+ ion in a wide temperature range (4–300 K). The energies of 40 crystal-field levels of the Sm3+ ion are determined for the ground and excited multiplets in the spectral region of 2000–10 000 cm–1. The spectra revealed two magnetic phase transitions: at temperature of TN = 35 K, magnetic ordering occurs, and at temperature of TR = 8.5 K—spin-reorientation transition. The ground Kramers doublet of the Sm3+ ion splits only at a low-temperature phase transition. The data obtained on the energy states of the ground multiplet 6H5/2 of the Sm3+ ion are used to calculate the contribution of samarium to the heat capacity of Cu3Sm(SeO3)2O2Cl. [ABSTRACT FROM AUTHOR]