Zero-field splitting¶

Warning

Work in progress

This tutorial calculates the zero-field splitting for the NV center in diamond and bi-radicals.

gpaw.zero_field_splitting.zfs(calc, method=1)[source]

Zero-field splitting.

Calculate magnetic dipole coupling tensor in eV.

gpaw.zero_field_splitting.convert_tensor(D_vv, unit='eV')[source]

Convert 3x3 tensor to D, E and easy axis.

Input tensor must be in eV and the result can be returned in eV, μeV, MHz or 1/cm according to the value of unit (must be one of “eV”, “ueV”, “MHz”, “1/cm”).

```>>> D_vv = np.diag([1, 2, 3])
>>> D, E, axis, _ = convert_tensor(D_vv)
>>> D
4.5
>>> E
0.5
>>> axis
array([0., 0., 1.])
```

Examples¶

Diamond NV- center¶

For a NV center in a cubic supercell, the D and E values are presented below with and without relaxaing the cell. The experimental value is around 2880 MHz.

atoms

relaxed

D (MHz)

E(MHz)

62

False

2286

4.66e-11

62

True

1551

2.34e-09

214

False

2365

7.48e-05

214

True

1731

2.56e-06