Large acoustic polaron states and bifurcation in three coupled parallel molecular chains

We consider the properties of the large acoustic polarons in a media composed of three parallel coupled identical macromolecular chains in an equilateral triangular arrangement. The existence of the truly three-dimensional large polarons has been demonstrated. Their appearance demands the complex interference of the effects of the reduced dimensionality, the nature and strength of the interchain coupling and particular geometrical arrangement of molecular chains. Different types of solutions were found and criteria for their existence were formulated in terms of the dimensionless interchain coupling parameter.