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In this article, theoretical interpretation and prediction of the optical properties of nanodiamond (ND) particles', containing various luminescence centers, was made. Particularly, nitrogen, and chromium atoms embedded into the diamond crystal lattice were modeled. In the case of nitrogen centers containing ND particles, the effect of various surface terminations (hydrogen and/or oxygen, fluorine) was also studied. To get a qualitative better understanding of the complicated and specific process of ND particles, luminescence using density functional theory, were modeled processes and states influencing the luminescence of ND particles.

Nanodiamond is a novel and promising material for in vitroand in vivoimaging in living cells. In this work, we studied using quantum chemical calculation methods how the various surface terminations affect the conditions for the fluorescence of nitrogenvacancy NV centers in nanodiamond particles. We worked with clusters containing between 35 and 86 atoms of carbon containing NV centers with different charge states of their vacancies NV−and NV0 and with different terminations: OH, H, NH2, carbonyl, carboxyl, and hydroxyl groups. The systems under study were modeled by DFTbased calculations using the Gaussian 09 and Turbomole5.10 program packages.

AbstractComplete set of infrared reflection and Raman scattering spectra of LaBGeO5and Pb5Ge3O11glasses and crystallised glasses was measured in a broad frequency and temperature range. Comparison with the spectra of crystals showed that the short range order in the glasses and in the corresponding crystals is very similar.

Polykrystalická diamantová vrstva (PCD) se jeví jako vhodná ochrana pro snížení chemické reaktivity zirkoniových slitin. Její aplikací by mohlo dojít k výraznému zvýšení odolnosti zirkonia proti vysokoteplotní korozi a rovněž vůči navodíkování. V této práci jsou zkoumány vzorky slitiny zirkonia Zry-2, které byly pokryty 300 nm tenkou vrstvou PCD a pre-exponovány v páře o teplotách 950 a 1150 °C. Pomocí ex-situ elektrochemické impedanční spektroskopie jsou studovány přenosové parametry a morfologie PCD vrstvy. Výsledky ukazují, že vzorky slitiny zirkonia Zry-2, které byly pokryty PCD vrstvou, korodují za vysokých teplot s nižší korozní rychlostí.