YANG Jianrong, TONG Guoping, YANG Hui, LU Kui, ZHANG Linxi. A STUDY OF THE VIBRATIONAL SPECTRA OF TWO-DIMENSIONAL POLYMERS[J]. Acta Polymerica Sinica, 2003,(3):337-342.
YANG Jianrong, TONG Guoping, YANG Hui, LU Kui, ZHANG Linxi. A STUDY OF THE VIBRATIONAL SPECTRA OF TWO-DIMENSIONAL POLYMERS[J]. Acta Polymerica Sinica, 2003,(3):337-342.DOI:
Polyacetylene and polyaniline usually have one-dimensional character because their interchain coupling interaction is weak.As the pressure increases
the interaction also increases and interchain energy gap reduces so that interchain distance b decreases and interchain elastic distance increases.When b approaches the lattice constant a
the polymer of one-dimensional chains becomes a two-dimensional compound lattice structure after considering their interchaln coupling action
and new physical properties may arise.In this paper
the second-nearest-neighbor interactions between lattice chains of polyacetylene and polyaniline are considered
and the two-dimensional compound lattice model is adopted.Using the method of lattice dynamics
the dispersion curves of these polymers under different mass ratio are calculated and three kinds of lattice chain interactions are also investigated.The changes of spectra in high symmetric curves under BZ are discussed.We also plot the curve under the various mass ratios.The results show that the two-dimensional compound lattice polymer has two acoustic branches and two optical branches
and the increase of interchain coupling interaction can destroy the effects of aberration of dimerization
and cause the dimensional effect.If interchain coupling interaction is weak and vibration of interchain direction can be neglected
the polymer becomes one-dimensional chain and has only an optical branch and an acoustic branch.