Atomistic Insights into Liquid Crystals of Board-Like Molecules via Molecular Dynamics Simulation Díaz Acosta, Adrián Adroher Benítez, Irene Zéron, Iván Patti, Alessandro Liquid crystals Molecular Dynamics All authors acknowledge funding from Junta de Andalucía-Consejería de Universidad, Investigación e Innovación (project P21_00015) and the Carlos I Institute of Theoretical and Computational Physics for providing computational time on the supercomputer PROTEUS. I.A.B. acknowledges project A-EXP-359-UGR23, cofunded by Junta de Andalucía-Consejería de Universidad, Investigación e Innovación and by the European Union under the FEDER Andalucía 2021-2027 Programme. A. P. acknowledges a “María Zambrano Senior” fellowship, funded by the NextGenerationEU/PRTR programme of the European Union and the Spanish Ministry of Universities. As the temperature decreases, rigid anisotropic molecules that usually incorporate polar groups, aromatic rings or multiple bonds, orient along a common direction, eventually forming liquid-crystalline phases under specific thermodynamic conditions. This study explores the phase behaviour and dynamics of board-shaped mesogens with a 1,4,5,8-tetraphenyl-anthraquinone core and four lateral arms forming an oligo(phenyleneethynylene) scaffold. These molecules are promising candidates for forming the elusive biaxial nematic phase. Through atomistic molecular dynamics simulations, we observe the formation of nematic and smectic liquid crystals, in qualitative agreement with experimental observations. To characterise the structure, we compute pair correlation functions along relevant symmetry directions and the nematic order parameter, which indicate a dominant uniaxial ordering with very weak biaxiality. Additionally, we analyse the dynamics of our board-shaped mesogens along and perpendicular to the nematic director, revealing intriguing non-Gaussian behaviour and dynamical heterogeneities, with coexisting slow and fast molecules. Building on our recent simulations at the colloidal scale, which demonstrated that monodisperse board-like particles are unable to form biaxial nematics while polydisperse particles can, we hypothesise that similar behaviour may occur at the molecular scale in mixtures of molecules. Although pure-component molecular systems reveal weak biaxiality, our findings suggest that investigating mixtures of the most promising candidates, those molecules that form nematic or smectic phases, could uncover conditions conducive to the formation of biaxial nematic liquid crystals. 2024-12-04T08:33:15Z 2024-12-04T08:33:15Z 2024-11-21 journal article Díaz Acosta, Adrián et al. Atomistic Insights into Liquid Crystals of Board-Like Molecules via Molecular Dynamics Simulation. American Institute of Physics. 2024 https://hdl.handle.net/10481/97680 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ open access Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License American Institute of Physics