Studies on the nature and pressure evolution of phase transitions in 1-adamantylamine and 1-adamantanol

Paulina Jesionek; Barbara Hachuła; Dawid Heczko; Taoufik Lamrani; Karolina Jurkiewicz; Magdalena Tarnacka; Maria Książek; Kamil Kamiński; Ewa Kamińska

doi:10.1016/j.saa.2023.122794

Studies on the nature and pressure evolution of phase transitions in 1-adamantylamine and 1-adamantanol

Spectrochim Acta A Mol Biomol Spectrosc. 2023 Oct 15:299:122794. doi: 10.1016/j.saa.2023.122794. Epub 2023 May 3.

Authors

Paulina Jesionek¹, Barbara Hachuła², Dawid Heczko³, Taoufik Lamrani⁴, Karolina Jurkiewicz⁵, Magdalena Tarnacka⁴, Maria Książek⁴, Kamil Kamiński⁴, Ewa Kamińska⁶

Affiliations

¹ Institute of Chemistry, Faculty of Science and Technology, University of Silesia in Katowice, Szkolna 9, 40-007 Katowice, Poland; Department of Pharmacognosy and Phytochemistry, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiellonska 4, 41-200 Sosnowiec, Poland.
² Institute of Chemistry, Faculty of Science and Technology, University of Silesia in Katowice, Szkolna 9, 40-007 Katowice, Poland. Electronic address: barbara.hachula@us.edu.pl.
³ Department of Statistics, Department of Instrumental Analysis, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, ul. Ostrogorska 30, 41-200 Sosnowiec, Poland.
⁴ Institute of Physics, Faculty of Science and Technology, University of Silesia in Katowice, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.
⁵ Institute of Physics, Faculty of Science and Technology, University of Silesia in Katowice, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland. Electronic address: karolina.jurkiewicz@us.edu.pl.
⁶ Department of Pharmacognosy and Phytochemistry, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiellonska 4, 41-200 Sosnowiec, Poland.

PMID: 37167743
DOI: 10.1016/j.saa.2023.122794

Abstract

In this paper, several experimental techniques, i.e., differential scanning calorimetry, X-ray diffraction, Fourier transform infrared, Raman, and broadband dielectric spectroscopy were applied to study the nature of the phase transitions in 1-adamantylamine (1-NH₂-ADM, C₁₀H₁₇N) and 1-adamantanol (1-OH-ADM, C₁₀H₁₆O). Calorimetric measurements showed one and three endothermic peaks in thermograms for the latter and the former substance, respectively. Indeed, results of spectroscopic investigations indicated that the observed thermal events in 1-NH₂-ADM correspond to transitions between various plastic crystal (PC) phases (I, II, III, IV), while the endothermic process in 1-OH-ADM can be assigned to a phase transition between the PC and the ordinary crystal (OC). Especially interesting were the outcomes of dielectric studies carried out both at ambient and high-pressure conditions, during heating and cooling cycles. They showed: i) noticeable changes in the frequency dependencies of the imaginary (ε^'') and real (ε^') parts of the complex dielectric permittivity that occurred around temperatures of the characteristic endothermic events detected by the calorimetry, and ii) significant fluctuations of ε^'' and ε^' at pressures attributed to the respective phase transitions. Moreover, the pressure coefficients of the phase transition temperatures were estimated to be approximately equal to 0.2 K/MPa for both compounds. In turn, volume variation (ΔV) at the PC (II)-PC (III) and PC (III)-PC (IV) transition temperatures for 1-NH₂-ADM was essentially different than ΔV for the PC-OC transition in 1-OH-ADM.

Keywords: 1-Adamantanol; 1-Adamantylamine; Dielectric measurements; High-pressure; Phase transition; Plastic crystal.