【摘要】 本文中我们理论设计了一类硅取代并苯,并且采用DFT和CASSCF方法计算并分析了其结构和电子性质。研究表明,硅取代并苯从一个环到四个环仍保持闭壳层单重态(CS态)基态属性,扩展到五个环即硅取代并五苯时,体系开始以开壳层破损态单重态(BS态)为能量基态并具有明显的双自由基性质,这与母体并五苯是闭壳层\单重态基态的情况截然不同。同时,其BS态能量基态导致其内部具有明显的反铁磁性,这使得硅取代并五苯具有了构建磁性可控反铁磁性材料的应用潜力。这项工作为设计开发并苯基磁性材料提供了一个合理思路,具有一定的应用意义。更多还原

【Abstract】 In this work,the parent and silicon-modified acenes are computationally studied.Calculations predict that the silicon-modified pentacene begins to possess the open-shell broken-symmetry(BS)singlet ground state with obvious diradical character.In the meanwhile,the smaller silicon-modified acenes(from silicon-modified benzene to silicon-modified tetracene)are still closed-shell singlets.As we know,the pentacene has been widely applied in the field of electronic devices.But its closed-shell singlet ground state limits its application in the magnetic field.Our silicon modification makes silicon-modified pentacene exhibit the open-shell broken-symmetry(BS)singlet diradical ground state with obvious antiferromagnetic character,further offers silicon-modified pentacene the potential to build magnetic-controllable antiferromagnetic materials.更多还原