Saleem Yasser, Steenbock Torben, Alhadi Emha Riyadhul Jinan, Pasek Weronika, Bester Gabriel, Potasz Pawel
Institut für Physikalische Chemie, Universität Hamburg, Grindelallee 117, D-20146 Hamburg, Germany.
Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Toruń, Poland.
Nano Lett. 2024 Jun 5;24(24):7417-23. doi: 10.1021/acs.nanolett.4c01604.
We show that the origin of the antiferromagnetic coupling in spin-1 triangulene chains, which were recently synthesized and measured by Mishra et al. ( 2021, 598, 287-292), originates from a superexchange mechanism. This process, mediated by intertriangulene states, opens the possibility to control parameters in the effective bilinear-biquadratic spin model. We start from the derivation of an effective tight-binding model for triangulene chains using a combination of tight-binding and Hartree-Fock methods fitted to hybrid density functional theory results. Next, correlation effects are investigated within the configuration interaction method. Our low-energy many-body spectrum for = 2 and = 4 triangulene chains agree well with the bilinear-biquadratic spin-1 chain antiferromagnetic model when indirect coupling processes and superexchange coupling between triangulene spins are taken into account.
我们表明，最近由米什拉等人（2021年，598卷，287 - 292页）合成并测量的自旋为1的三角烯链中反铁磁耦合的起源，源自一种超交换机制。这个由三角烯间态介导的过程，为控制有效双线性 - 二次方自旋模型中的参数提供了可能性。我们首先使用拟合到杂化密度泛函理论结果的紧束缚和哈特里 - 福克方法的组合，推导三角烯链的有效紧束缚模型。接下来，在组态相互作用方法中研究关联效应。当考虑三角烯自旋之间的间接耦合过程和超交换耦合时，我们对于N = 2和N = 4三角烯链的低能多体谱与双线性 - 二次方自旋 - 1链反铁磁模型吻合得很好。
