The present invention discloses new polymers which can assume an accordion-like conformation of the backbone. These polymers are prepared by the copolymerization of two difuntional, chemically precoupled precursors to chromophoric units. The resulting polymers have a head-to-head, tail-to-tail topology (a syndioregic arrangement of rigid units along the polymer backbone), and the molecular units are designed to fold into an "accordion" conformation. This useful microstructure (a three-dimensional conformation) forms spontaneously (self-assembles); or, it can be brought about by field-assisted processing. Films and fibers of these polymers have useful second-order nonlinear optical properties, and may be used for the modulation and switching of optical communications signals.