Monte Carlo simulations of polymers with nearest- and next nearest-neighbor interactions on square and cubic lattices

• Autor(a) principal: Rodrigues, Nathann T
• Data de Publicação: 2014
• Outros Autores: Oliveira, Tiago J
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://dx.doi.org/10.1088/1751-8113/47/40/405002; http://www.locus.ufv.br/handle/123456789/23773
• topic: Theta polymers; Coil–globule transition; Interacting self-avoiding walks; Monte Carlo simulations

We study a generalized interacting self-avoiding walk (ISAW) model with nearest- and next nearest-neighbor (NN and NNN) interactions on square and cubic lattices. In both dimensions, the phase diagrams show coil and globule phases separated by continuous transition lines. Along these lines, we calculate the metric νt, crossover phgrt and entropic γt exponents, all of them in good agreement with the exact values of the Θ universality class. Therefore, the introduction of NNN interactions does not change the class of the ISAW model, which still exists even for repulsive forces. The growth parameters μt are shown to change monotonically with temperature along the Θ-lines. In the square lattice, the Θ-line has an almost linear behavior, which was not found in the cubic one. Although the region of repulsive NNN interactions, with attractive NN ones, leads to stiff polymers, no evidence of a transition to a crystalline phase was found.