Research output: Contribution to journal › Article › peer-review
High-temperature behavior of the UV-luminescent sodalite-type natural compound Na8(Al6Si6O24)(HS)2: Comparative study by in situ single-crystal X-ray diffraction and Raman spectroscopy. / Shchipalkina, Nadezhda V. ; Vereshchagin, Oleg S. ; Chukanov, Nikita V. ; Gorelova, Liudmila A. ; Bocharov, Vladimir N. ; Pekov, Igor V. .
In: Journal of Solid State Chemistry, Vol. 323, 124067, 01.07.2023.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - High-temperature behavior of the UV-luminescent sodalite-type natural compound Na8(Al6Si6O24)(HS)2: Comparative study by in situ single-crystal X-ray diffraction and Raman spectroscopy
AU - Shchipalkina, Nadezhda V.
AU - Vereshchagin, Oleg S.
AU - Chukanov, Nikita V.
AU - Gorelova, Liudmila A.
AU - Bocharov, Vladimir N.
AU - Pekov, Igor V.
PY - 2023/7/1
Y1 - 2023/7/1
N2 - The in situ single-crystal X-ray diffraction and Raman spectroscopy were performed for a sapozhnikovite Na8(Al6Si6O24)(HS)2, a rare mineral with sodalite-type crystal structure. The crystal chemical analysis and calculation of thermal expansion coefficients based on the refinement of Na8(Al6Si6O24)(HS)2 crystal structures in the temperature range of 300–1273 K show that this sodalite-type compound undergoes: (1) reversible phase transition P 3n ↔ Pm n at 1223 K, (2) drastic increase of linear expansion coefficient at 1173 K, (3) non-elastic behavior of sapozhnikovite framework after cooling. The temperature dependencies of the unit-cell parameters were divided into two parts and described by quadratic a = 8.911(12) – 0.000018(33)T + 0.000000138(22)T2 (from 300 to 1173 K) and linear a = 7.765(13) + 0.001130(11)T (from 1173 to 1273 K) polynomial functions. Raman spectroscopy data reveal the partial transformations of the extra-framework HS− anion by follows reactions: 6HS–→ S3•– + 3H2S (gas) and 2HS– – 2e → S22− + 2H+. These transformations may cause the observed discontinuity in the thermal expansion curve for sapozhnikovite at 1173 K with drastic increase of linear expansion coefficient and not fully elastic behavior of framework after removal of temperature exposure. After the heat treatment experiments (300–1273 K) the HS− anion restores in the β-cage of sapozhnikovite crystal structure. In the synthetic analogue of sapozhnikovite the heat treatment leads to the irreversible transformation according to the reactions: 2HS– + 2.5O2 (gas) → SO42− + 0.25S4 + H2O (gas) and 2HS– + 3.5O2 (gas) → SO42− + SO2 (gas) + H2O (gas). The orange luminescence of Na8(Al6Si6O24)(HS)2 is stable up to the 1073 K.
AB - The in situ single-crystal X-ray diffraction and Raman spectroscopy were performed for a sapozhnikovite Na8(Al6Si6O24)(HS)2, a rare mineral with sodalite-type crystal structure. The crystal chemical analysis and calculation of thermal expansion coefficients based on the refinement of Na8(Al6Si6O24)(HS)2 crystal structures in the temperature range of 300–1273 K show that this sodalite-type compound undergoes: (1) reversible phase transition P 3n ↔ Pm n at 1223 K, (2) drastic increase of linear expansion coefficient at 1173 K, (3) non-elastic behavior of sapozhnikovite framework after cooling. The temperature dependencies of the unit-cell parameters were divided into two parts and described by quadratic a = 8.911(12) – 0.000018(33)T + 0.000000138(22)T2 (from 300 to 1173 K) and linear a = 7.765(13) + 0.001130(11)T (from 1173 to 1273 K) polynomial functions. Raman spectroscopy data reveal the partial transformations of the extra-framework HS− anion by follows reactions: 6HS–→ S3•– + 3H2S (gas) and 2HS– – 2e → S22− + 2H+. These transformations may cause the observed discontinuity in the thermal expansion curve for sapozhnikovite at 1173 K with drastic increase of linear expansion coefficient and not fully elastic behavior of framework after removal of temperature exposure. After the heat treatment experiments (300–1273 K) the HS− anion restores in the β-cage of sapozhnikovite crystal structure. In the synthetic analogue of sapozhnikovite the heat treatment leads to the irreversible transformation according to the reactions: 2HS– + 2.5O2 (gas) → SO42− + 0.25S4 + H2O (gas) and 2HS– + 3.5O2 (gas) → SO42− + SO2 (gas) + H2O (gas). The orange luminescence of Na8(Al6Si6O24)(HS)2 is stable up to the 1073 K.
KW - High temperature single-crystal diffraction
KW - Hydrosulfide anion
KW - Luminescence
KW - Sodalite type compounds
KW - Thermal expansion
KW - Thermal transformations
KW - Thermo-Raman spectroscopy
UR - https://www.mendeley.com/catalogue/75cbd8d5-e7d9-3f6f-9573-b577123e2d26/
U2 - 10.1016/j.jssc.2023.124067
DO - 10.1016/j.jssc.2023.124067
M3 - Article
VL - 323
JO - Journal of Solid State Chemistry
JF - Journal of Solid State Chemistry
SN - 0022-4596
M1 - 124067
ER -
ID: 104500672