Thermal expansion of sodium fluoride and sodium bromide

First-principles relativistic calculation for 4f–5d transition energy of Ce3+ in various fluoride hosts

“…(a) NaF [15] Fm3m [20] Pm3m Ba 2+ O h 12 0.908 (g) LiYF 4 [21] I4 1 /a Y 3+ S 4 8 1.053 (h) LiCaAlF 6 [22] P31c Ca 2+ S 6 6 1.004 (i) LiSrAlF 6 [23] P31c Sr 2+ S 6 6 0.931 (j) CeF 3 [24] P3c1 C 2 11 0.000 (k) YF 3 [25] Pnma Y 3+ C s 9 1.051 (l) LaF 3 [26] P3c1 La 3+ C 2 11 0.992 (m) KMgF 3 [27] Pm3m K + O h 12 0.899 (n) BaMgF 4 [28] Cmc21 Ba 2+ C s 8 0.899 (o) NaMgF 3 [29] Pnma Na + C s 12 0.981…”

Extended temperature dependence of elastic constants in cubic crystals

“…Table 1 Temperature coefficients TC IJ (10 6 Pa K À1 ) and T 2 C IJ (10 3 Pa K À2 ) for some cubic crystals at room temperature. The data on the elastic constants and temperature coefficients of linear expansion for NaCl were taken from [22,23], respectively, for KCl from [22,24], for KBr from [22,25], for NaBr from [22,26], for KF from [22,27], for AgCl from [22,28], for Au from [29,30], and for Ag from [29,31] number of cubic crystals. In particular, they are important if the temperature dependence deviates from linear behavior.…”

Thermodynamic optimization of the (Na2O+SiO2+NaF+SiF4) reciprocal system using the Modified Quasichemical Model in the Quadruplet Approximation

“…NaF, also known as villiaumite, has one allotropic form with the rocksalt crystal structure (cF8, Fm 3m [111]), while Na 2 SiF 6 presents two allotropic forms: a low-temperature trigonal phase (hP27, P3 2 1 [112]) and a high-temperature cubic structure [113] (no crystallographic data). Solid SiF 4 is not stable in the considered ranges of temperature and pressure of the present assessment and has not been included.…”