Correlated electronic states of nitrogen-based transition-metal pseudo-oxides

本文对三维过渡金属碳二亚胺MNCN （M = Mn-Cu）的密度泛函电子结构进行了数值分析，并结合有关其光学和磁性能的实验，清楚地表明，用标准（DFT）固态方法不能很好地处理其真实的电子结构。特别是，局部多电子态和共振价键（RVB）态很可能参与其中。因此，我们建议在有效哈密顿晶体场（EHCF）和RVB方法的基础上对上述材料族进行详细的理论研究。特别是，一些透明MNCN和M(NCNH)2材料（M = Fe-Ni）的光谱以及铁化合物的Mößbauer光谱将被计算，以建立它们的多电子性质。此外，将对相CuNCN进行数值和分析研究，例如通过中子衍射，SQUID， EPR， NMR和其他光谱技术来定量建模和了解其（可能）RVB基态的性质。

The numerical analysis of the density-functional electronic structures of the 3d transition-metal carbodiimides MNCN (with M = Mn–Cu) as confronted with experiments touching upon their optical and magnetic properties clearly indicates that their true electronic structures cannot be properly dealt with using standard (DFT) solid-state approaches. In particular, local many-electron states and also resonating-valence bond (RVB) states are very likely to be involved. We thus propose to perform a detailed theoretical study of the above family of materials, on the basis of the effective Hamiltonian crystal-field (EHCF) and RVB approaches. In particular, the optical spectra of some of the transparent MNCN and M(NCNH)2 materials (M = Fe–Ni) as well as the Mößbauer spectra of the iron compounds will be calculated in order to establish their many-electron nature. Also, the phase CuNCN will be studied both numerically and analytically such as to quantitatively model and understand the nature ofits (presumably) RVB ground state as indicated by neutron diffraction, SQUID, EPR, NMR and other spectroscopic techniques.