Spin contamination errors on spin-polarized density functional theory/plane-wave calculations for crystals of one-dimensional materials

Abstract

An estimation scheme is established for the spin contamination error (SCE) in spin-polarized density functional theory calculations with the plane-wave basis for crystals of one-dimensional materials. The size consistency of the scheme was confirmed via H-chain models, and the accuracy was confirmed by the comparison with the reported experimental values. The scheme was applied to real systems, specifically, tribromo-trioxotriangulene and [Ni(cyclohexanediamine)2Br]Br2 crystals. It clarified the SCEs on the energies of calculated models (0.049–3.093 eV). The presented scheme will enable the appropriate investigation and design of functional materials of nano (molecular) wire, superconductors, catalysts, quantum computing, and so on.

Diradical Characters of s-Indaceno[1,2,3-cd;5,6,7-c’d’]Diphenalene with and without Interaction with MgO(001)

“…The used DFT-D3 parameters were optimised using Becke-Jonson damping [35]. It is known that spin contamination error affects the calculated results of diradical states by single-referenced method, such as Kohn-Sham DFT [7,8,36]. Then, the errors in biradical molecules were corrected via approximate spin projection scheme for DFT/plane-wave calculation (AP-DFT/plane-wave scheme) [20][21][22][23]36].…”

Flavones’ and Flavonols’ Antiradical Structure–Activity Relationship—A Quantum Chemical Study

“…This step includes removing a single hydrogen atom from each hydroxyl group and running computations at UB3LYP/6-31+G(d,p), retaining an implicit water solvent in two ways: with and without geometry optimization. Spin contamination values of open shell DFT results were checked, as they may interfere with the outcome [45,46]. All were in a range of <0.7500, 0.7511> after spin annihilation.…”

First-principles study of CO2 hydrogenation to formic acid on single-atom catalysts supported on SiO2

“…37 Moreover, spin contamination errors (SCE) were considered for the broken symmetric states (BS) and corrected using Yamaguchi's equation 38 with modification for DFT/plane-wave calculations. 39,40 where LS and HS denote low spin state and high spin state, respectively. The subscript exact indicates the exact value (the eigenvalue of Ŝ 2 ), and U means the value estimated by spin-polarized (unrestricted) calculations.…”

“…37 Moreover, spin contamination errors (SCE) were considered for the broken symmetric states (BS) and corrected using Yamaguchi's equation 38 with modification for DFT/plane-wave calculations. 39,40 SCE ¼…”