Surface phase transitions in one-dimensional channels arranged in a triangular cross-sectional structure: Theory and Monte carlo simulation

P. M. PASINETTI; F. ROMÁ; J. L. RICCARDO; A. J. RAMIREZ-PASTOR

JOURNAL OF CHEMICAL PHYSICS

Año: 2006 vol. 125 p. 214705 - 214714

0021-9606

Monte Carlo simulations and finite-size scaling analysis have been carried out to study the critical behavior in a submonolayer lattice-gas of interacting monomers adsorbed on one-dimensional channels arranged in a triangular cross-sectional structure. Two kinds of lateral interaction energies have been considered:
1 wL, interaction energy between nearest-neighbor particles adsorbed along a single channel and
2 wT, interaction energy between particles adsorbed across nearest-neighbor channels. We focus on the case of repulsive transverse interactions
wT
0, where a rich variety of structural orderings are observed in the adlayer, depending on the value of the parameters kBT/wT
1 wL, interaction energy between nearest-neighbor particles adsorbed along a single channel and
2 wT, interaction energy between particles adsorbed across nearest-neighbor channels. We focus on the case of repulsive transverse interactions
wT
0, where a rich variety of structural orderings are observed in the adlayer, depending on the value of the parameters kBT/wT
2 wT, interaction energy between particles adsorbed across nearest-neighbor channels. We focus on the case of repulsive transverse interactions
wT
0, where a rich variety of structural orderings are observed in the adlayer, depending on the value of the parameters kBT/wT
wT
0, where a rich variety of structural orderings are observed in the adlayer, depending on the value of the parameters kBT/wTkBT/wT
being kB the Boltzmann constant and wL /wT. For wL /wT=0, successive planes are uncorrelated, the system is equivalent to the triangular lattice, and the well-known
33 
33* ordered phase is found at low temperatures and a coverage, , of 1/3 2/3. In the more general casebeing kB the Boltzmann constant and wL /wT. For wL /wT=0, successive planes are uncorrelated, the system is equivalent to the triangular lattice, and the well-known
33 
33* ordered phase is found at low temperatures and a coverage, , of 1/3 2/3. In the more general case
33 
33* ordered phase is found at low temperatures and a coverage, , of 1/3 2/3. In the more general case, of 1/3 2/3. In the more general case
wL /wT0, a competition between interactions along a single channel and a transverse coupling between sites in neighboring channels leads to a three-dimensional adsorbed layer. Consequently, the
33 and
33* structures “propagate” along the channels and new ordered phases appear in the adlayer. Each ordered phase is separated from the disordered state by a continuous order-disorder phase transition occurring at a critical temperature, Tc, which presents an interesting dependence with wL /wT. The Monte Carlo technique was combined with the recently reported free energy minimization criterion approach
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.wL /wT0, a competition between interactions along a single channel and a transverse coupling between sites in neighboring channels leads to a three-dimensional adsorbed layer. Consequently, the
33 and
33* structures “propagate” along the channels and new ordered phases appear in the adlayer. Each ordered phase is separated from the disordered state by a continuous order-disorder phase transition occurring at a critical temperature, Tc, which presents an interesting dependence with wL /wT. The Monte Carlo technique was combined with the recently reported free energy minimization criterion approach
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.
33 and
33* structures “propagate” along the channels and new ordered phases appear in the adlayer. Each ordered phase is separated from the disordered state by a continuous order-disorder phase transition occurring at a critical temperature, Tc, which presents an interesting dependence with wL /wT. The Monte Carlo technique was combined with the recently reported free energy minimization criterion approach
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.Tc, which presents an interesting dependence with wL /wT. The Monte Carlo technique was combined with the recently reported free energy minimization criterion approach
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.wL /wT. The Monte Carlo technique was combined with the recently reported free energy minimization criterion approach
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.
FEMCA F. Romá et al., Phys. Rev. B 68, 205407
2003 to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allows us to interpret the physical meaning of the mechanisms underlying the observed transitions.