Ab initio molecular dynamics simulation of methanol and acetonitrile: the effect of van der Waals interactions

• Autor(a) principal: Dias, Rafael F.
• Data de Publicação: 2019
• Outros Autores: Costa, Cleidineia C. da, Manhabosco, Taise M., Oliveira, Alan B. de, Matos, Matheus J. S., Soares, Jaqueline S., Batista, Ronaldo J. C.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1016/j.cplett.2018.10.085; http://www.locus.ufv.br/handle/123456789/23403
• topic: Methanol; Acetonitrile; Dynamics simulation

We employed PBE and BLYP semi-local functionals and the van der Waals density functional of Dion et al. (2004) (vdW-DF) to investigate structural properties of liquid acetonitrile and methanol. Among those functionals the vdW-DF is the only one that correctly predicts energy minima in inter-molecular interactions between acetonitrile molecules. We found that van der Waals interactions have a negligible effect on H-bonds in methanol chains. However, it significantly increases chain packing resulting in a more dense liquid in comparison to the other two functionals. The overall trend is that the vdW-DF tends to overestimate density and bulk modulus, meanwhile the semi-local functionals tend to underestimate density. Thus, van der Waals interactions play an important role in the properties of liquids in which much stronger dipole-dipole interactions are present.