Table 1 Tight-binding parameters for pyrochlore Pb\(_2\)X\(_2\)O\(_7\) (X = As, Sb, Sn).
From: New three-dimensional flat band candidate materials Pb2As2O7 and Pb2Sn2O7
| Â | Pb\(_2\)X\(_2\)O\(_7\) | |||||
|---|---|---|---|---|---|---|
X = As | X = Sb | X = Sn | ||||
\(\epsilon ,t\) | Distance | \(\epsilon ,t\) | Distance | \(\epsilon ,t\) | Distance | |
\(\epsilon ^\textrm{Pb}\) | \(-0.44\) | On-site | \(-0.57\) | On-site | \(-0.018\) | On-site |
\(\epsilon ^\textrm{X}\) | 0.78 | On-site | 1.49 | On-site | Â | Â |
\(t_1^{\mathrm {Pb-Pb}}\) | \(-0.18\) | 0.3535a | \(-0.26\) | 0.3535a | \(-0.13\) | 0.3535a |
\(t_2^{\mathrm {Pb-Pb}}\) | \(-0.06\) | 0.6142a | \(-0.02\) | 0.6142a | \(-0.05\) | 0.6142a |
\(t_1^{\mathrm {X{-}X}}\) | \(-0.34\) | 0.3535a | \(-0.36\) | 0.3535a | Â | Â |
\(t_2^{\mathrm {X{-}X}}\) | \(-0.06\) | 0.6142a | \(-0.04\) | 0.6142a | Â | Â |
\(t_1^{\mathrm {Pb{-}X}}\) | \(-0.06\) | 0.5a | \(-0.08\) | 0.5a | Â | Â |
\(t_2^{\mathrm {Pb{-}X}}\) | \(-0.01\) | 0.6142a | 0.02 | 0.6142a | Â | Â |
