Instabilities, thermal fluctuations, defects and dislocations in the crystal-R<sub>I</sub>-R<sub>II</sub> rotator phase transitions of <i>n</i>-alkanes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39851089.
- Also identified by DOI 10.1039/d4sm01170h.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The theoretical study of instabilities, thermal fluctuations, and topological defects in the crystal-rotator-I-rotator-II (X-R<sub>I</sub>-R<sub>II</sub>) phase transitions of <i>n</i>-alkanes has been conducted. First, we examine the nature of the R<sub>I</sub>-R<sub>II</sub> phase transition in nanoconfined alkanes. We propose that under confined conditions, the presence of quenched random orientational disorder makes the R<sub>I</sub> phase unstable. This disorder-mediated transition falls within the Imry-Ma universality class. Next, we discuss the role of thermal fluctuations in certain rotator phases, as well as the influence of dislocations on the X-R<sub>I</sub> phase transition. Our findings indicate that the herringbone order in the X-phase and the hexatic order in the R<sub>II</sub>-phase exhibit quasi-long-range characteristics. Furthermore, we find that in two dimensions, the unbinding of dislocations does not result in a disordered liquid state.