Formation energy puzzle in intermetallic alloys: Random phase approximation fails to predict accurate formation energies

Nepal, Niraj K.; Adhikari, Santosh; Neupane, Bimal; Ruzsinszky, Adrienn

doi:10.1103/physrevb.102.205121

Cited by 17 publications

(7 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nepal et al have proposed that the X-Y system is weakly-bonded when X and Y have completely filled d-bands, by assuming the B2 structure and performing DFT calculations [12,13]. Such combinations of X and Y include the Cu-Au, Cu-Zn and Cu-Pd systems, which are consistent with the present findings.…”

Section: B Cu-xsupporting

confidence: 90%

“…While the Cu and Au have the fcc structure as its ground state, the Cu-Au system forms several ordered structures depending on the mixing ratio: CuAu in the L1 0 structure and Cu 3 Au and CuAu 3 in the L1 2 structure. The DFT results were consistent with such observations, while the underestimation of the formation energy by a factor of two in the Cu-Au system and the missing of the L1 2 CuAu 3 along the tie line in the phase diagram have been reported [9][10][11][12][13].…”

Section: Introductionsupporting

confidence: 85%

See 1 more Smart Citation

Finding the stable structures of 2D hexagonal materials with Bayesian optimization: Beyond the structural relationship with 3D crystals in weakly-bonded binary systems

Ono¹

2022

Preprint

View full text Add to dashboard Cite

The graphene-graphite relationship in structural geometry is a basic principle to predict novel two-dimensional (2D) materials. Here, we demonstrate that this is not the case in binary metallic systems. We use the Bayesian optimization framework combined with the density-functional theory approach to determine the stable configuration of atomic species on a hexagonal plane. We show that the optimized structure of 2D Cu-Au exhibits the hexagonal lattice of a hexagonal ring of Cu atoms containing one Au atom, where the number of the Cu atoms is larger than that of the Au atoms in the unit cell, which is difficult to speculate from the atomic distribution of CuAu in the L10 structure. We also show that 2D Cu-X with X = Be, Zn, and Pd have hexagonal or elongated rings containing different atoms in the unit cell. Based on the binary Lennard-Jones model, we propose that such structures can appear for weakly-bonded systems located in between the phase-separated and strongly-bonded systems with the interatomic interaction energy between different species.

show abstract

Section: B Cu-xsupporting

confidence: 90%

Section: Introductionsupporting

confidence: 85%

Finding the stable structures of 2D hexagonal materials with Bayesian optimization: Beyond the structural relationship with 3D crystals in weakly-bonded binary systems

Ono¹

2022

Preprint

View full text Add to dashboard Cite

show abstract

“… is the minimum total energy of X , where this is determined by calculating the energy of the bcc, fcc, and hcp structures. Note that the functional dependence of the of ordered compounds has been studied in detail 41 – 44 . The use of the PBE functional can predict the value of accurately for strongly bonded systems, while it may underestimate for weakly bonded systems such as CuAu.…”

Section: Methodsmentioning

confidence: 99%

Metastability relationship between two- and three-dimensional crystal structures: a case study of the Cu-based compounds

Ono

2021

Sci Rep

View full text Add to dashboard Cite

Some of the three-dimensional (3D) crystal structures are constructed by stacking two-dimensional (2D) layers. To study whether this geometric concept, i.e., using 2D layers as building blocks for 3D structures, can be applied to computational materials design, we theoretically investigate the dynamical stability of copper-based compounds CuX (a metallic element X) in the B$$_h$$ h and L1$$_1$$ 1 structures constructed from the buckled honeycomb (BHC) structure and in the B2 and L1$$_0$$ 0 structures constructed from the buckled square (BSQ) structure. We demonstrate that (i) if CuX in the BHC structure is dynamically stable, those in the B$$_h$$ h and L1$$_1$$ 1 structures are also stable. Using molecular dynamics simulations, we particularly show that CuAu in the B$$_h$$ h and L1$$_1$$ 1 structures withstand temperatures as high as 1000 K. Although the interrelationship of the metastability between the BSQ and the 3D structures (B2 and L1$$_0$$ 0 ) is not clear, we find that (ii) if CuX in the B2 (L1$$_0$$ 0 ) structure is dynamically stable, that in the L1$$_0$$ 0 (B2) is unstable. This is rationalized by the tetragonal Bain path calculations.

show abstract

“…where ε j (CuX) is the total energy of CuX in the structure j. ε min (X) is the minimum total energy of X, where this is determined by calculating the energy of the bcc, fcc, and hcp structures. Note that the functional dependence of the E j of ordered compounds has been studied in detail [40][41][42][43]. The use of the PBE functional can predict the value of E j accurately for strongly bonded systems, while it may underestimate E j for weakly bonded systems such as CuAu.…”

Section: Discussionmentioning

confidence: 99%

Metastability relationship between two- and three-dimensional crystal structures: A case study of the Cu-based compounds

Ono

2021

Preprint

View full text Add to dashboard Cite

Some of the three-dimensional (3D) crystal structures are constructed by stacking two-dimensional (2D) layers. It remains unclear whether this geometric concept is related to the stability of ordered compounds and whether this can be used to computational materials design. Here, using first principles calculations, we investigate the dynamical stability of copper-based compounds CuX (a metallic element X) in the B h and L11 structures constructed from the buckled honeycomb (BHC) structure and in the B2 and L10 structures constructed from the buckled square (BSQ) structure. We demonstrate that (i) if CuX in the BHC structure is dynamically stable, those in the B h and L11 structures are also stable. Although the interrelationship of the metastability between the BSQ and the 3D structures (B2 and L10) is not clear, we find that (ii) if CuX in the B2 (L10) structure is dynamically stable, that in the L10 (B2) is unstable, analogous to the metastability relationship between the bcc and the fcc structures in elemental metals. The total energy curves for CuX along the tetragonal and trigonal paths are also investigated.

show abstract

Formation energy puzzle in intermetallic alloys: Random phase approximation fails to predict accurate formation energies

Cited by 17 publications

References 72 publications

Finding the stable structures of 2D hexagonal materials with Bayesian optimization: Beyond the structural relationship with 3D crystals in weakly-bonded binary systems

Finding the stable structures of 2D hexagonal materials with Bayesian optimization: Beyond the structural relationship with 3D crystals in weakly-bonded binary systems

Metastability relationship between two- and three-dimensional crystal structures: a case study of the Cu-based compounds

Metastability relationship between two- and three-dimensional crystal structures: A case study of the Cu-based compounds

Contact Info

Product

Resources

About