Theoretical investigation of the isomer shifts of theSn119Mössbauer isotope

The effect of alumina on the Sn2+/Sn4+ redox equilibrium and the incorporation of tin in Na2O/Al2O3/SiO2 melts

“…The smallest isomer shift known for Sn 4þ is )0.39 mm s À1 for K 2 SnF 6 [31] which has predominantly ionic bonds, whereas crystalline SnO 2 (routile) reveals an isomeric shift of 0.0 mm s À1 [32]. It is important to realize in this context that the tin ion even in the nominal Sn 4þ compound SnO 2 has a significant density of 5s electrons at the nucleus [34] and also of 5p and 5d electrons as revealed by electronic structure calculations [35]. Hence, the bonding of Sn 4þ in the glass is to be considered predominantly ionic, however, with a significant covalent contribution.…”

First principles calculation of Mössbauer isomer shift

“…Typically, scalar-relativistic quantum chemical formalism was employed for the interpretation of 119 Sn Mössbauer data. In these calculations, the contact density was obtained from averaging of the scalar-relativistic total density obtained in solid-state X␣ or DFT calculations inside a sphere of nuclear charge radius [52,53,[98][99][100][101][102][103][104]. Similarly to the case of 57 Fe, majority of these calculations have been carried out for a few compounds of the target element.…”

“…On the basis of comparison between the relativistic and the non-relativistic isomer shifts obtained with the use of the same formalism, it was found that inclusion of relativity is important for obtaining accurate results from molecular (cluster) models. It is noteworthy that scalar-relativistic solid-state calculations are routinely carried out in the study of Mössbauer parameters of crystalline solids [53,55,56,87,[100][101][102]105,106,131].…”

“…These early works resulted in a number of empirical relationships between the occupation numbers of the valence orbitals of resonating atom and its isomer shift. At a later stage, calculations on cluster models [103,104,[133][134][135][136][137][138] as well as solid-state calculations [53,[100][101][102]105,106,131] have been carried out.…”

Role of surface passivation in the formation of Dirac states at polar surfaces of topological crystalline insulators: The case of SnTe(111)

“…1(c)]. The experimental band gap in SnTe is strongly dependent on the hole carrier concentration and varies in the range of 0.10-0.30 ± 0.05 eV [31][32][33][34][35][36]. Both theoretical values of the bulk gap, obtained within the GGA and GW approaches, lie in the middle of the experimental range.…”