Table 2.
EXAFS Curve-Fitting Results for 9-P, 10, and 11a
| sample | fit no. | R (Å) | σ2 × 106 (Å2) | ΔE0 (eV) | Fb | |
|---|---|---|---|---|---|---|
| 9-P | 1 | 5 O/Nc | 2.10 | 1200 | −6.2 | 0.497 |
| 4 C | 3.06 | 660 | ||||
| 2 | 4 O/N | 2.12 | 900 | −3.9 | 0.400 | |
| 2 C/O | 2.50 | 830 | ||||
| 4 C | 3.07 | 600 | ||||
| 3 | 4 O/N | 2.12 | 900 | −3.8 | 0.393 | |
| 2 C/O | 2.49 | 860 | ||||
| 0.2 Fe | 2.92 | 650 | ||||
| 4 C | 3.09 | 510 | ||||
| 10 | 4 | 6 O/N | 2.05 | 1300 | 0.7 | 0.331 |
| 5 C | 3.04 | 340 | ||||
| 5 | 6 O/N | 2.05 | 1280 | 0.1 | 0.280 | |
| 1 Fed | 3.03 | 400 | ||||
| 5 Cd | 3.00 | 1520 | ||||
| 11 | 6 | 6 O/N | 2.02 | 840 | 0.7 | 0.298 |
| 5 C | 3.00 | 270 | ||||
| 7 | 6 O/N | 2.02 | 820 | 0.0 | 0.241 | |
| 1 Fed | 3.00 | 400 | ||||
| 5 Cd | 2.94 | 1160 |
a
Errors are estimated to be 25% for coordination numbers and 0.01 − 0.03 Å for distances.
b
Error (F) is defined as F = [Σk6(χexptl — χcalcd)2]/Σk6| χexptl2].
c
Scatterers differing by Z = ±1 are not distinguishable by EXAFS. The first element in a pair indicates the type of atom used to model the backscattered wave in the theoretical fit.
d
Due to a high degree of correlation, the errors for the Fe—Fe and Fe—C distances at ∼3.0 Å are estimated to be around 0.05 Å.