Selected best EXAFS fits for the Zn, Cd, Hg, Pb-site in CmΔZntA166–794a.
| Metal-site | Shelld (N) | r d (Å) | σ 2 c d (×10−3 Å−2) | R-factord (%) | Red. χ2 |
|---|---|---|---|---|---|
| Zn-site | 2N/O | 1.99(0) | 2(0) | 2.91 | 24.8 |
| 2S | 2.29(0) | 4(0) | |||
| Cd-site | 2N/O | 2.32(2) | 5(0) | 1.73 | 6.4 |
| 2S | 2.48(2) | 2(2) | |||
| Hg-site | 1N/O | 2.48(3) | 5(0)b | 1.55 | 7.5 |
| 2S | 2.33(1) | 3(0) | |||
| Pb-site | 1N/O | 2.52(2) | 1(2) | 7.34 | 17.7 |
| 2S | 2.67(2) | 9(1) |
a
r – Inter atomic distance (in parentheses are mean-square deviations). σ2 – Debye–Waller factor (in parentheses are mean-square deviations in DW factor).
b
σ 2 was fixed during fitting.
c
- Values reported as 0 represent small positive numbers after 3 significant figures (e.g. 0.003 with 0.002 error = 3(2); 0.0004 with 0.0001 error = 0(0)).
d
The mean-square deviation values in parentheses are related to fit precision, while R-factors are fitting errors. These are distinct from model accuracies, which are expected to be larger (approx. 0.02 Å for r, and approx. 20% for N and corresponding Debye–Waller factors – σ2). Typically, N and σ2 are highly correlated, and N was fixed in curve fitting to limit the correlation.