Table 1
Initial setup for the calculations: relative positions x, y and z in the CeBa2Cu3TaO7 unit cell, muffin-tin radii rMT (in a.u.), valence (val.) and semicore (sem.) orbitals included in the initial basis set. Note that O(5) is treated as an empty sphere.
| Site | x | y | z | rMT | val. | sem. |
|---|---|---|---|---|---|---|
| Ce | 0.5 | 0.5 | 0.5000 | 2.800 | 6s 6p 5d 4f | 5p |
| Ba | 0.5 | 0.5 | 0.1843 | 3.592 | 6s 5p 5d 4f | 5s |
| Ba | 0.5 | 0.5 | -0.1843 | 3.592 | 6s 5p 5d 4f | 5s |
| Cu(1) | 0.0 | 0.0 | 0.0000 | 1.872 | 4s 4p 3d | |
| Cu(2) | 0.0 | 0.0 | 0.3556 | 1.985 | 4s 4p 3d | |
| Cu(2) | 0.0 | 0.0 | -0.3556 | 1.985 | 4s 4p 3d | |
| O(1) | 0.0 | 0.5 | 0.0000 | 1.837 | 2s 2p | |
| O(2) | 0.5 | 0.0 | 0.3773 | 1.721 | 2s 2p | |
| O(2) | 0.5 | 0.0 | -0.3773 | 1.721 | 2s 2p | |
| O(3) | 0.0 | 0.5 | 0.3789 | 1.760 | 2s 2p | |
| O(3) | 0.0 | 0.5 | -0.3789 | 1.760 | 2s 2p | |
| O(4) | 0.0 | 0.0 | 0.1584 | 1.660 | 2s 2p | |
| O(4) | 0.0 | 0.0 | -0.1584 | 1.660 | 2s 2p | |
| O(5) | 0.5 | 0.0 | 0.0000 | 1.801 | 2s 2p |
Fig. 1
Total energy versus cell volume curve for Cel23 system from the LSDA calculations (Birch-Murnaghan fit).
Fig. 2
Total energy versus cell volume curve for Ce123 system from the LSDA+U calculations (Birch-Murnaghan fit).
Fig. 3
Total energy versus cell volume curve for Ce123 system at the finite temperature T = 500 K from the LSDA+DMFT calculations (Birch-Murnaghan fit; spline interpolation used as a guide to the eye).
Fig. 4
Total energy versus cell volume curve for Ce123 system at the finite temperature T = 700 K from the LSDA+DMFT calculations (Birch-Murnaghan fit; spline interpolation used as a guide to the eye).
Fig. 5
Pressure versus cell volume from Birch-Murnaghan equation of state for LSDA+DMFT at T = 500 K.
Table 2
The equilibrium cell volume V0, lattice parameter a0 and bulk modulus B0 of Ce123 obtained from the Birch-Murnaghan fits in LSDA, LSDA+U and LSDA+DMFT.
| T [K] | V0 [a.u.3] | a0 [a.u.] | B0 [GPa] | |
|---|---|---|---|---|
| LSDA | 0 | 1230.29 | 7.3771 | 140.7 |
| LSDA+U | 0 | 1198.66 | 7.3134 | 160.9 |
| LSDA+DMFT | 500 | 1271.77 | 7.4591 | 178.0 |
| LSDA+DMFT | 700 | 1197.29 | 7.3106 | 441.2 |
Fig. 6
Ce 4f “spin-up” and “spin-down” density of states against a background of the total density of states of the Ce123 system for different volumes (expressed as V/Vo ratios) from the LSDA+DMFT at T = 700 K. The Fermi level EF was put at 0 eV.