Thermally-induced crystallization behaviour of 80GeSe2–20Ga2Se3 glass as probed by combined X-ray diffraction and PAL spectroscopy

Positronics of subnanometer atomistic imperfections in solids as a high-informative structure characterization tool

“…Indeed, under the condition that I 3 * ≅ I 3 host , the decreasing I 2 * intensities in Equation 6 provide negative values for I int . Thus, in full agreement with previous conclusion extracted from x2-decomposed PAL spectra [10], the I int. intensities attain firstly negative values, this process being quickly saturated in a 50-h annealed sample.…”

“…= −0.014), while host and 50-h annealed glasses are under obvious void fragmentation (appearance of new positron-trapping sites). The bulk positron lifetimes in all samples are smaller than previously observed τ b ≅ 0.260 ns [10], corresponding to positron trapping occurring just in the nanocrystalline particles itself. The appeared/disappeared interfacial free-volume voids are not too large, since the characteristic value of τ int = 0.27 to 0.30 ns lifetime can be associated with typical volumes of mono-or diatomic vacancies in chalcogenide-like systems [1,3,[14][15][16].…”

Studies of CdI2-Bi3 microstructures with optical methods, atomic force microscopy and positron annihilation spectroscopy

“…Measurements were performed at room temperature (293 K) and ambient humidity (35 %). A series of a few independent experiments were connected with samples of the same prehistory to exclude data scatter because of differences between actual status of samples and uncontrolled instabilities in the experimental setting of PALS spectrometer [11]. The obtained results agreed well with each other within experimental uncertainties, being no more than ±0.005 ns in lifetimes and ±0.01 in component intensities.…”

Positron annihilation characterization of free volume in micro- and macro-modified Cu0.4Co0.4Ni0.4Mn1.8O4 ceramics

“…The error-bars are ±0.03 ns for lifetimes, ±0.01 arb. units for intensities and ±0.01 ns -1 for positron trapping rate of defects [41,44]. Let's try to discuss the results (Table 1) obtained within positron trapping model by accepting that structural peculiarities of spinel ceramics is associated mainly in the first PAL component (τ 1 , I 1 ).…”