Building Ouro, using AI to search for room-temp superconductors and rare-earth free permanent magnets.
Fe13Co3N1 (requested SG: P622 #177, calculated SG: P1 #1, optimized: 400 steps, cell relaxed (isotropic))
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); imaginary modes detected; min freq = -3.89 THz
Phase diagram of Fe10Co5N2; e_above_hull: 0.612570 eV/atom; predicted_stable: False
Fe10Co5N2 (requested SG: P6mm #183, calculated SG: P1 #1, optimized: 400 steps, cell relaxed (isotropic))
Phase diagram of Fe12Co4N; e_above_hull: 0.223703 eV/atom; predicted_stable: False
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); no imaginary modes; min freq = -0.04 THz
Fe12Co4N1 (requested SG: P-31m #162, calculated SG: P1 #1, optimized: 339 steps, cell relaxed (isotropic))
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); no imaginary modes; min freq = -0.25 THz
Phase diagram of Fe4Co4N; e_above_hull: 0.173983 eV/atom; predicted_stable: False
Fe4Co4N1 (requested SG: P4/mmm #123, calculated SG: P1 #1, optimized: 165 steps, cell relaxed (isotropic))
Phase diagram of Fe3Co3N2; e_above_hull: 2.389667 eV/atom; predicted_stable: False
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); imaginary modes detected; min freq = -8.43 THz
Fe3Co3N2 (requested SG: P4/mmm #123, calculated SG: P1 #1, optimized: 400 steps, cell relaxed (isotropic))
Increased demand for high-performance permanent magnets in the electric vehicle and wind turbine industries has prompted the search for cost-effective alternatives. Nevertheless, the discovery of new magnetic materials with the desired intrinsic and extrinsic permanent magnet properties presents a significant challenge. Traditional Density Functional Theory (DFT) accurately predicts intrinsic permanent magnet properties such as magnetic moments, magneto-crystalline anisotropy constants, and exchange interactions. However, it cannot compute extrinsic macroscopic properties, such as coercivity (Hc), which are influenced by factors like microscopic defects and internal grain structures. Although micromagnetic simulation helps compute Hc, it overestimates the values almost by an order of magnitude due to Brown’s paradox. To circumvent these limitations, we employ Machine Learning (ML) methods in an extensive database obtained from experiments, DFT calculations, and micromagnetic modeling. Our novel ML approach is computationally much faster than the micromagnetic simulation program, the mumax3. We successfully utilize it to predict Hc values for materials like cerium-doped Nd2Fe14B, and subsequently compare the predicted values with experimental results. Remarkably, our ML model accurately identifies uniaxial magnetic anisotropy as the primary contributor to Hc. With DFT calculations, we predict the Nd-site dependent magnetic anisotropy behavior in Nd2Fe14B, confirming 4f-site planar and 4g-site uniaxial to crystalline c-direction in good agreement with experiment. The Green’s function atomic sphere approximation calculated a Curie temperature (TC) for Nd2Fe14B that also agrees well with experiment. Paper by Churna Bhandari, Gavin N. Nop, Jonathan D.H. Smith, Durga Paudyal
Cell + Ionic relaxation with Orb v3; 0.03 eV/Å threshold; final energy = -71.0098 eV; energy change = 0.0000 eV; symmetry: P3m1 → P3m1
Crystal from description (space group: P3m1 #156, crystal system: trigonal, point group: 3m)
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); no imaginary modes; min freq = -0.00 THz
Phonon band structure (supercell [2, 2, 2], Δ=0.01 Å); no imaginary modes; min freq = -0.07 THz
Phase diagram of Fe2CoNiB; e_above_hull: 0.162034 eV/atom; predicted_stable: False
Fe4Co2Ni2B2 (requested SG: P3 #143, calculated SG: P1 #1, optimized: 166 steps, cell relaxed (isotropic))