Nudge elastic band investigations of triazine nanothread formation mechanism

Nanothreads are novel 1D carbon-based nanomaterials, that yield ordered 2D van der Waals packing. Some nanothreads are also ordered along the thread. They are synthesized via High-Pressure treatments of a variety of small aromatic molecules such as benzene, furan, triazine, pyridazine, among others [1-4].

Nanothread structure and the synthesis mechanism (meant here in the organic reaction mechanism context) are of particular interest since better knowledge of these topics leads to higher control on the synthesis process towards a nanothread with engineered properties. Recently a pyridazine nanothread as been proposed yet the formation mechanism was not studied. Here we propose to study employing mostly Density Functional Theory. In particular the applicant will use nudge elastic band to investigate the reaction mechanism from pyridazine to the nanothread, finding the transition states that lead to the transformation. Gaining insight in reaction mechanism as performed for triazine nanothread, see fig 1 [3]. The applicant will also investigate this process from a molecular point of view, studying the reaction of two, three and four pyridazine molecules under pressure with the XPPCM method as implemented in Gaussian16.

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[2] B. Chen, R. Hoffmann, N. Ashcroft, J. Badding, E. Xu, and V. Crespi, Linearly Polymerized Benzene Arrays As Intermediates, Tracing Pathways to Carbon Nanothreads, J. Am. Chem. Soc. 2015, 137 (45) 14373-14386.

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