@article {48719,
	title = {Molecular mechanisms underlying nanowire formation in pristine phthalocyanine},
	journal = {Physical Chemistry Chemical Physics},
	volume = {25},
	year = {2023},
	month = {NOV},
	pages = {30259-30268},
	type = {Article},
	abstract = {<p>
	Understanding the molecular processes of nanowire self-assembly is crucial for designing and controlling nanoscale structures that could lead to breakthroughs in functional materials. In this work, we focus on pristine phthalocyanines as a representative example of mesogenic supramolecular assemblies and have analyzed the formation of nanowires using classical molecular dynamics simulations. In the simulations, the molecules spontaneously form multi-columnar structures resembling supramolecular polymers that subsequently grow into more ordered aggregates. These self-assemblies are concentration dependent, leading to the formation of multi-columnar, dynamic aggregates at higher concentrations and nanowires at lower concentrations. The multi-columnar assemblies on a whole are more disordered than the nanowires, but have locally ordered domains of parallel facing molecules that can fluctuate while maintaining their overall shape. The nanowire formation at lower concentrations involves the initial interaction and clustering of randomly oriented phthalocyanine molecules, followed by the merging of small clusters into elongated segments and the eventual formation of a stable nanowire. We observe three main conformers in these self-assemblies, the parallel, T-shaped and edge-to-edge stacking of the phthalocyanine dimers. We calculate the underlying free energy landscape and show that the parallel conformers form the most stable configuration which is followed by the T-shaped and edge-to-edge dimer configurations. The findings provide insights into the mechanisms and pathways of nanowire formation and a step towards the understanding of self-assembly processes in supramolecular mesogens. Understanding the molecular processes of nanowire self-assembly of phthalocyanine molecules.</p>
},
	issn = {1463-9076},
	doi = {10.1039/d3cp03512c},
	author = {Pinjari, Aadil and Saraf, Deepashri and Sengupta, Durba}
}
@article {48463,
	title = {Surface-induced demixing of self-assembled isomeric mixtures of citral},
	journal = {Journal of Molecular Liquids},
	volume = {381},
	year = {2023},
	month = {JUL },
	pages = {121803},
	type = {Article},
	abstract = {<p>
	The self-assembly of organic molecules and their interactions with metal surfaces have been of considerable interest, both for developing novel functional materials and for understanding fundamental design principles of nanostructures. In this study, we investigate the solution and surface-induced self-assembly of two stereoisomers of citral molecules (geranial and neral) using atomistic molecular dynamics simulations. We demonstrate that the morphology of the aggregates in water is concentration dependent (ranging from distorted spherical to slab-like aggregates) but independent of isomer effects. The isomeric mixtures of citral indicate homogeneous mixing based on differential density maps and high values of Shannon entropy. Interestingly, surface-confinement of citral aggregates on a Cu(111) surface leads to phase segregation and demixing of the two isomers that is more apparent in the surface-bound monolayer in comparison to the adjacent layers. Positional ordering and formation of domains are observed over a series of isomeric citral mixtures with varying compositions, as indicated by high differential density and low values of Shannon entropy. Our work provides new insights into molecular self-assembly of organic molecules in nanostructures and metal-organic overlayers.(c) 2023 Elsevier B.V. All rights reserved.</p>
},
	keywords = {Citral, Isomers, Metal-organic interactions, molecular dynamics, Self-assembly, Shannon entropy},
	issn = {0167-7322},
	doi = {10.1016/j.molliq.2023.121803},
	author = {Saraf, Deepashri and Prakash, Shikha and Pinjari, Aadil and Pujari, Bhalchandra and Sengupta, Durba}
}
