Here we report synthesis and characterization of Mg1−xScxB2 (0.12Tc>6 K. We find that the Sc doping moves the chemical potential through the 2D/3D electronic topological transition (ETT) in the σ band where the "shape resonance" of interband pairing occurs. In the 3D regime beyond the ETT we observe a hardening of the E2g Raman mode with a significant line-width narrowing due to suppression of the Kohn anomaly over the range 0

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Thermoluminescence spectra have been recorded for crystals of pure KMgF3, KMgF3:Pb2+ and KMgF3:Eu3+, with the aim of identifying new phosphors for radiation dosimetry. Glow peaks, due to thermal activation of colour centres formed by ß or ? irradiation, were measured in both pure and doped materials. Typical thermoluminescence signals due to Pb2+ or Eu3+ impurities have been obtained, besides those of the host KMgF3. The intensity of the thermoluminescence peaks is not very high in Pb2+-doped samples, while Eu3+ ions are found to be excellent activators, as usual for rare earth impurities. In KMgF3:Eu3+ a new prominent peak has been found very efficient for monitoring radiation doses, because of its high sensitivity, good stability over time and elevated activation energy.

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