Results for “Ca(NiP)2” | Engineering Papers

DOE OSTI2020

Materials Data on Ca(NiP)2 by Materials Project

CaNi2P2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ca2+ is bonded in a distorted body-centered cubic geometry to eight equivalent P3- atoms. All Ca–P bond lengths are 3.00 Å. Ni2+ is bonded to four equivalent P3- atoms to form a mixture of edge and corner-sharing NiP4 tetrahedra. All Ni–P bond lengths are 2.29 Å. P3- is bonded in a 9-coordinate geometry to four equivalent Ca2+, four equivalent Ni2+, and one P3- atom. The P–P bond length is 2.32 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2025

Hamiltonian parameter inference from resonant inelastic x-ray scattering with active learning

Identifying model Hamiltonians is a vital step toward creating predictive models of materials. Here, in this study, we combine Bayesian optimization with the EDRIXS numerical package to infer Hamiltonian parameters from resonant inelastic x-ray scattering (RIXS) spectra within the single atom approximation. To evaluate the efficacy of our method, we test it on experimental RIXS spectra of NiPS 3 , NiCl 2 , Ca 3 ⁢LiOsO 6 , and Fe 2⁢ O 3 , and demonstrate that it can reproduce results obtained from hand-fitted parameters to a precision similar to expert human analysis while providing a more systematic mapping of parameter space. Our work provides a key first step toward solving the inverse scattering problem to extract effective multi-orbital models from information-dense RIXS measurements, which can be applied to a host of quantum materials. We also propose atomic model parameter sets for two materials, Ca 3⁢ LiOsO 6 and Fe 2⁢ O 3 , that were previously missing from the literature.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗