[14p-D215-1~7] 【CS.5】 Code-sharing Session of 7.4 & 9.5

▲ [14p-D215-5] Ground state determination of LiVX₂ system using Diffusion Monte Carlo

〇(D)Genki Imam Prayogo¹, Aleksey Ushakov², Tom Ichibha³, Kenta Hongo^1,5,6, Sergey Streltsov², Ryo Maezono^1,4 (1.JAIST, 2.Inst. Met. Phys., 3.ORNL, 4.RIKEN, 5.NIMS, 6.PRESTO, JST)

Keywords:Diffusion Monte Carlo, frustrated antiferromagnet

The LiVX₂ system (X: O, S, Se) is an example of a Heisenberg antiferromagnet with the geometrical frustration existing on the triangular lattice of its vanadium layer. While LiV(O,S)₂ has been observed to host a VBS state at low temperature, indicated by a metal-to-insulator transition and trimerization of the vanadium lattice, LiVSe₂ was not found to exhibit such transition. With its strong electronic correlation, methods based on one-body theory, such as DFT, often failed to correctly describe its properties, as was found in our preliminary calculations. We employed a new approach based on Diffusion Monte Carlo, which is based on many-body wave function, thus expected to correct for this. We performed a static energetic comparison between the trimerization structures, in both unpolarized and collinear spin-polarized formalization, as well as charge density analysis in the frustrated vanadium layer, benchmarking both approach against experimental data.