Heat capacity and enthalpy of phase transitions of α- and β-modifications of lead fluoride

Effect of iso- and heterovalent cation substitutions on the superionic Faraday transition in fluorite-type modification β-PbF-=SUB=-2-=/SUB=-

“…In case of a β-PbF 2 crystal, the temperatures and length of the transition are T λ tr ≈ 720 K, T α tr ≈ 620 K and T tr ≈ 100 K respectively. The results obtained for the β-PbF 2 crystal are in good agreement with the literature data [16,[24][25][26][27][28].…”

“…In comparison with them, the fluorite modification β-PbF 2 is the most low-melting (melting point T f us = 1098 ± 5 K). For it, the maximum heat capacity temperatures according to different authors are 705 [24], 710 [25], 715 [26], 718 [27] and 721 K [28] (mean T λ tr = 715 ± 10 K). The temperature T α tr corresponding to the beginning of the structural disorder of the anionic sublattice is 597 ± 12 K [16].…”

Highly decoupled ionic and protonic solid electrolyte systems, in relation to other relaxing systems and their energy landscapes

“…4 by SnCl 2 . The conductivity jump [38] is considerably sharper than that of SnCl 2 and is accompanied by a heat capacity spike that is so sharp that it resembles a kinetically spread-out first order transition [39]. Yet the crystal symmetry does not change.…”

Temperature-dependent potential for the molecular dynamics of the superionic conductor β-PbF2

“…In previous study [ 11 ], the values employing only the Walker's potential showing a higher value (80.49 J K −1 mol −1 ) than the experimental one (76.81 ± 0.51 J K −1 mol −1 at 400 K) and above 700 K a chaotic behavior arise, without exhibiting a phase transition. In this work, a lower value , than the experimental is calculated (52.3 J mol −1 K −1 at 500 K against 79.87 J mol −1 K −1 measured by Volodich et al., [ 22 ]), and a phase transition is predicted. The difference between the values (experimental and theoretical) is the non-existence of a nominal value in the literature for temperatures above room temperature.…”