Electron Transport in Disordered Molecular Systems

这是一项更新补助金，由 材料研究和化学。 理论项目聚焦于 的输运和自旋性质的作用 粒状金属和导电聚合物。 关于颗粒的工作 metals金属represents代表a new新thrust推力to this ongoing持续project项目. 杂质 波段和缩放参数提出了解释 实验观察到的颗粒金属的导电性。 是 显示了如何杂质带模型的粒状金属可以 应用于导电聚合物聚苯胺。 此外， 用相互作用电子模型来解释磁 聚苯胺的性质 研究将在 聚乙炔和绝缘体上结构无序的作用- 金属过渡 最后，研究了从两个到两个的交叉， 聚合物聚吡咯高氯酸盐的一维动力学 将进行。 %%% 在真实的材料中，无序通过杂质或 原子或分子的错位， 晶体或化学结构。 这种紊乱可能会产生深远的 对材料性能的影响。 的理解 各种类型的无序及其对材料的影响， 这是材料科学家面临的一个重大挑战。 拟议研究 将研究一种新的方法来研究紊乱对两种类型的人的影响， 导电聚合物和粒状金属。 两 这些材料具有重要的应用，并构成了强大的 理论上的困难

This is a renewal grant jointly funded by the Divisions of Materials Research and Chemistry. The theoretical project focuses on the role of disorder on the transport and spin properties of granular metals and conducting polymers. The work on granular metals represents a new thrust to this ongoing project. Impurity band and scaling arguments are proposed to explain the experimentally observed conductivity in granular metals. It is shown how the impurity band model for granular metals can be applied to conducting polymer polyaniline. In addition, an interacting electron model is used to explain the magnetic properties of polyaniline. Studies will be conducted on polyacetylene and the role of structural disorder on the insulator- metal transition. Finally, a study of the crossover from two- to one-dimensional dynamics in the polymer poly-pyrolle perchlorate will be undertaken. %%% In real materials disorder manifests itself through impurities or the misplacement of atoms or molecules in an otherwise perfect crystal or chemical structure. This disorder can have profound effects on the properties of materials. The understanding of various types of disorder and its influence on materials represents a major challenge to materials scientists. The proposed research will study a novel approach to the effects of disorder on two types of systems: conducting polymers and granular metals. Both of these materials have important applications and pose formidable theoretical difficulties.