Table 1.
EXAFS curve fitting results for Zn- and Co-BcII.a
| Fit | 4 M-N/O 0.5 M-S 2 | 2 M-Hisb | M-M | % ISc | % IMd | Refined M-M CN |
|---|---|---|---|---|---|---|
| Zn 0.5 1.0 2.0 |
2.02 (5.0) 2.28 (8.0) 2.03 (6.6) 2.28 (6.0) 2.03 (6.3) 2.27 (2.6) |
2.95 (1.6) 3.21 (5.0) 4.12 (9.0) 4.41 (21) 2.93 (0.6) 3.18 (2.0) 4.08 (13) 4.44 (14) 2.90 (3.1) 3.18 (5.8) 4.08 (11) 4.43 (15) |
3.41 (13) 3.41 (10) 3.42 (8.3) |
37 36 41 |
24 30 47 |
0.12 0.30 0.91 |
| Co 0.5 1.0 2.0 |
2.03 (6.9) 2.30 (1.7) 2.06 (6.1) 2.30 (3.7) 2.09 (1.3) 2.31 (5.4) |
2.94 (4.2) 3.24 (15) 4.03 (12) 4.28 (18) 2.94 (2.2) 3.25 (14) 4.02 (10) 4.28 (16) 2.93 (1.8) 3.19 (14) 4.08 (14) 4.32 (12) |
3.56 (8.8) 3.55 (6.0) 3.55 (5.4) |
79 61 23 |
39 43 27 |
0.15 0.33 0.96 |
Distances (Å) and disorder parameters (in parentheses, σ2 (10−3 Å2)) shown derive from integer or half-integer coordination number fits to filtered EXAFS data [k = 1.5–12.5 Å−1; R = 0.2–4.2 Å].
Imidazole multiple scattering paths represent combined paths, as described previously (see Materials and Methods).
Percentage reduction of the fit residual for a first shell fit that includes 0.5 S scatterers over one that utilizes only N/O scatterers (% IS). See Supporting Information for details.
Percentage reduction of the fit residual for a fit that includes 4 N/O and 0.5 S scatterers in the first shell, the outer shell scattering from two coordinated imidazoles and a metal-metal vector, compared to one that lacks the metal-metal vector (% IM). See Supporting Information for details.