THEORETICAL CHEMISTRY STUDIES OF CONDUCTING POLYMER SYSTEMS

THEORETICAL CHEMISTRY TECHNIQUES ARE USED TO PROVIDE FUNDAMENTAL UNDERSTANDING OF THE MOLECULAR REQUIREMENTS FOR ACHIEVING CONDUCTIVE PROPERTIES IN POLYMER SYSTEMS AND IN A LATER STAGE TO ADDRESS THE REQUIREMENTS FOR ACHIEVING NONLINEAR OPTICAL PROPERTIES. IT IS PROPOSED TO DEDUCE THE CONDUCTION MECHANISM BY CALCULATING THE CONDUCTIVITY TENSOR DIRECTLY AND ANALYZING THE DIFFERENT CONTRIBUTIONS TO THIS QUANTITY. NOVEL APPROACHES TO THE CALCULATION OF THE NECESSARY PROPAGATORS MAKE POSSIBLE A DIRECT CONSIDERATION OF THE CONDUCTIVITY TENSOR. THE KEY DIFFERENCE WITH PREVIOUS TREATMENTS IS THAT WE CONSIDER THE FULL ELECTRON-NUCLEAR DYNAMICS WITHOUT AD HOC USE OF BORON-OPPENHEIMER APPROXIMATION. INITIALLY, DURING PHASE I, A WORK CODE WILL BE DEVELOPED FOR THE CALCULATION OF THE ELECTRIC CONDUCTIVITY TENSOR USING A SINGLE DETERMINENTAL STATE FOR THE ELECTRONS AND CLASSICAL NUCLEI. ALSO DURING PHASE I AS A VALIDATION OF THE CODE WE WILL INVESTIGATE THE SOLUTION MECHANISM IN POLACETYLENE FROM THE AB INITIO TIME-DEPENDENT VIEWPOINT AND STUDY THE EVOLUTION OF THE SOLITON EXCITATION TO VERIFY WHETHER IT RETAINS ITS SOLITAN SHAPE. THE CODE WILL BE WRITTEN SUCH THAT DURING LATER PHASES OF THIS WORK IT CAN BE USED FOR GENERAL POLYMERIC SYSTEMS.