Department of Chemistry , Yonsei University , 50 Yonsei-ro Seodaemun-gu , Seoul 03722 , Korea.
Departments of Chemistry and of Physics , University of California , Irvine , California 92697 , United States.
J Chem Theory Comput. 2018 May 8;14(5):2304-2311. doi: 10.1021/acs.jctc.7b01196. Epub 2018 Apr 12.
All-electron fixed-node diffusion Monte Carlo provides benchmark spin gaps for four Fe(II) octahedral complexes. Standard quantum chemical methods (semilocal DFT and CCSD(T)) fail badly for the energy difference between their high- and low-spin states. Density-corrected DFT is both significantly more accurate and reliable and yields a consistent prediction for the Fe-Porphyrin complex.
全电子固定节点扩散蒙特卡罗法为四个 Fe(II) 八面体配合物提供了自旋能隙基准。标准量子化学方法（半局域密度泛函理论和 CCSD(T)）在其高低自旋态之间的能量差上表现得非常糟糕。密度校正的密度泛函理论既更准确可靠，又对 Fe-卟啉配合物给出了一致的预测。
