Journal of Physical Studies 3(1), 60–69 (1999)
DOI: https://doi.org/10.30970/jps.03.60

MONTE CARLO STUDY OF A MONOMOLECULAR FILM OF A CHEMICALLY ASSOCIATING POLYMERIZING FLUID ADSORBED ON CRYSTALLINE LATTICES

Yu. Duda^1,*, O. Pizio¹, S. Sokolowski², N. Batina³
¹Instituto de Química de la UNAM, Circuito Exterior, Coyoacán 04510, México, D.F.
²Computer Laboratory, Faculty of Chemistry, Marie Curie–Sklodowska University, 200-31 Lublin, Poland
³Departmento de Fisica, Universidad Autonoma Metropolitana/Iztapalapa, 09430, Mèxico, Distrito Federal
^*Permanent address: Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine, Lviv-11, Ukraine

We consider a model for a monomolecular film of a polymerizing fluid adsorbed on a crystalline surface and study it using NVT Monte Carlo simulations. The model represents a two–dimensional chemically associating fluid of hard discs with center–center repulsion and site–site attraction, such that with increasing association energy discs polymerize in the external heterogeneous field due to a crystalline surface. It is shown that both the valence angle between attractive sites and the association energy influence the monolayer structure. We have performed a comparison of the results for the homogeneous surface (Yu. Duda et al., J.~Coll. Interface Sci. {\bf 194}, 68 (1997)) and the (100) single crystal plane is chosen to elucidate the effect of a substrate crystalline symmetry on the polymerization of species. Analysis of complexes that are formed due to association in terms of the fractions of singly and doubly bonded particles, of average numbers of chains and rings and of their size is presented. The average end to end distance, the radius of gyration and the persistence length of the products of polymerization are calculated. The dependencies of the monolayer structure on density, on the fluid–solid energy and on the valence angle are investigated.