A Topological Approach to Organic Superconductors and Ferromagnets

这个项目由堪萨斯州立大学的Andrzej Rajca在有机动力学项目中进行，旨在开发具有超导和铁磁性质的有机化合物。目前已知的例子很少，这种性质通常局限于无机固体。具有类金属性质的有机物的使用将提供丰富的可能性，因为易于制造和随后通过标准的有机合成方法对性质进行修改。由于分子和固体的电子结构和键合受到拓扑结构（和对称性）的影响，因此将采用拓扑方法研究有机超导体和铁磁体。将制备具有高度简并、占比最高、非成键分子轨道的多碳离子、自由基和自由基共轭碳氢化合物。这些轨道的简并和唯一离域具有拓扑起源而非对称起源。首先，将测试关于特殊拓扑结构对电荷分布、基态多重度和其他分子性质影响的理论预测。第二步，制备固体；在费米能级的态密度，带宽度，和其他重要的固体性质将得到，并与他们的分子对应物进行比较。最后，固体将被检查有关铁磁性和超导性。

This project by Andrzej Rajca at Kansas State University within the Organic Dynamics Program, is aimed at the development of organic compounds with superconducting and ferromagnetic properties. Very few examples are currently known, with such properties most often confined to inorganic solids. The use of organics with metallic-like properties will provide a wealth of possibilities due to ease of fabrication and subsequent modification of properties by standard methods of organic synthesis. Because the electronic structure and bonding of molecules and solids is affected by topology (and symmetry), a topological approach to organic superconductors and ferromagnets will be employed. Multi-carbanions, radicals, and radical anions of pi-conjugated hydrocarbons with highly degenerate highest occupied, non-bonding molecular orbitals will be prepared. The degeneracy and unique delocalization of these orbitals have a topological rather than symmetry origin. First, theoretical predictions about the impact of the special topology on the charge distribution, ground state multiplicities, and other molecular properties will be tested. Second, solids will be prepared; density of states at the Fermi level, band width, and other important solid state properties will be obtained and compared to their molecular counterparts. Finally, the solids will be examined with respect to ferromagnetism and superconductivity.