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Yerezhep D, Akylbayeva A, Golikov O, Sokolov DY, Shinbayeva A, Aldiyarov AU. Analysis of Vibrational Spectra of Tetrafluoroethane Glasses Deposited by Physical Vapor Deposition. ACS OMEGA 2023; 8:19567-19574. [PMID: 37305244 PMCID: PMC10249381 DOI: 10.1021/acsomega.3c00985] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/17/2023] [Indexed: 06/13/2023]
Abstract
This paper presents the results obtained in the study of structural phase transitions in thin films of R134A. The samples were condensed on a substrate by physical deposition of R134A molecules from the gas phase. Structural phase transformations in samples were investigated by observing the changes in characteristic frequencies of Freon molecules in the mid-infrared range with the help of Fourier-transform infrared spectroscopy. The experiments were carried out in the temperature range from 12 to 90 K. A number of structural phase states, including glassy forms, were detected. The changes in thermogram curves at fixed frequencies of half-widths of absorption bands of R134A molecules were revealed. These changes indicate a large bathochromic shift of these bands at frequencies of ν = 842 cm-1, ν = 965 cm-1, and ν = 958 cm-1 and a hypsochromic shift of the bands at frequencies of ν = 1055 cm-1, ν = 1170 cm-1, and ν = 1280 cm-1 at temperatures from T = 80 K to T = 84 K. These shifts are related to the structural phase transformations in the samples.
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Affiliation(s)
- Darkhan Yerezhep
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, 050040 Almaty, Kazakhstan
- Satbayev
University, 22 Satbayev
str., 050013 Almaty, Kazakhstan
- Institute
of Physics and Technology, Satbayev University, Ibragimov str., 11, 050032 Almaty, Kazakhstan
| | - Aigerim Akylbayeva
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, 050040 Almaty, Kazakhstan
- Kazakhstan
Institute of Standardization and Metrology Committee of Technical
Regulation and Metrology Ministry of Trade and Integration of the
Republic of Kazakhstan, Mangilik El Avenue, 11, 010000 Astana, Kazakhstan
| | - Oleg Golikov
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, 050040 Almaty, Kazakhstan
| | - Dmitriy Yurievich Sokolov
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, 050040 Almaty, Kazakhstan
- Almaty
Technological University, Tole Bi Avenue, 100, 050012 Almaty, Kazakhstan
| | - Ainura Shinbayeva
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, 050040 Almaty, Kazakhstan
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Sokolov D, Yerezhep D, Vorobyova O, Golikov O, Aldiyarov AU. Infrared Analysis and Effect of Nitrogen and Nitrous Oxide on the Glass Transition of Methanol Cryofilms. ACS OMEGA 2022; 7:46402-46410. [PMID: 36570311 PMCID: PMC9773807 DOI: 10.1021/acsomega.2c05090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/18/2022] [Indexed: 06/13/2023]
Abstract
Methanol plays an important role in studying the structure and dynamics of hydrogen bonds in alcohols and other physiologically important compounds in the condensed state. The physical vapor deposition method and two-beam interferometry make it possible to study the structure of polyatomic molecules, the nature and character of intermolecular interactions, and the internal structure of various compounds. Thus, it becomes possible to analyze changes in the internal structure of substances near the points of their phase transitions and glass transitions at ultralow temperatures. In this work, we have studied the effect of nitrogen and nitrous oxide on the dependence of refractive indices of methanol on temperature and on structural-phase transformations upon heating from 16 to 160 K.
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Affiliation(s)
- Dmitriy
Yurievich Sokolov
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, Almaty050040, Kazakhstan
- Almaty
Technological University, Tole Bi Avenue, 100, Almaty050012, Kazakhstan
| | - Darkhan Yerezhep
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, Almaty050040, Kazakhstan
| | - Olga Vorobyova
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, Almaty050040, Kazakhstan
- Almaty
Technological University, Tole Bi Avenue, 100, Almaty050012, Kazakhstan
| | - Oleg Golikov
- Al-Farabi
Kazakh National University, Al-Farabi Avenue, 71, Almaty050040, Kazakhstan
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