The role of electronic and structural properties in the high-pressure reaction of pseudo-stilbenes to double core carbon nanothreads

This thesis investigates the relationship between electronic and structural properties in pressure-induced transformations of pseudo-stilbenes into one-dimensional saturated carbon nanothreads. This work focuses on the high-pressure synthesis of carbon nanothreads using the diamond anvil cell (DAC), which provides the extreme uniaxial stress (up to several tens of GPa) necessary for inducing polymerization in selected organic precursor molecules, specifically pseudo-stilbenes. These precursors, including compounds like stilbene and bibenzyl, are distinguished by their dual aromatic rings linked by varying chemical moieties, offering a potential way to functionalize carbon nanothreads while maintaining high stability of the entire scaffold. Pseudo-stilbenes thus offer prospects for creating double-core carbon nanothreads, where the molecular bridge between aromatic rings can grant unique electronic and optical properties, potentially suitable for photonics, optoelectronics, and high-strength composites. Through a series of analyses, being Fourier-transform infrared (FTIR) and Raman spectroscopy, two-photon absorption (TPA) induced fluorescence spectroscopy, and X-ray diffraction, the study investigates the structural and vibrational evolutions in these compounds under compression. The results show that each precursor undergoes distinctive changes as pressure increases, with significant rearrangements in electronic density and molecular conformation at critical pressure points that lead to nanothread formation.