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Updated: Aug 2, 2025

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Binuclear spin-crossover [Fe(bt)(NCS)2]2(bpm) complex: A study using first principles calculations
Koussai Lazaar1, Fatma Aouaini2, Saber Gueddida3
1Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025 Evry-Courcouronnes, France.
Abstract:
The spin-crossover [Fe(bt)(NCS)2]2(bpm) complex is studied using spin-polarized density functional theory within the generalized gradient approximation, the Hubbard U and the weak van der Waals interactions in conjunction with the projector augmented wave method in its molecular and periodic arrangements. It is shown that the considered complex has three magnetic configurations [high spin state (HS)-HS, HS-low spin state (LS), and LS-LS] corresponding to those observed experimentally after two transition temperatures Tc (1) of 163 K and Tc (2) of 197 K. For the HS-HS magnetic state, we found that the two Fe centers are antiferromagnetically coupled for both molecular and periodic structures in good agreement with the experimental observations. Our results show that the computed total energy difference between the magnetic state configurations of the considered Fe2 complex is significantly smaller compared to those reported in the literature for other mono- or binuclear compounds.
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