Table 3.
Geometries of the various structures obtained
| Structure | BS | TPSS/def2-SV(P) fixed protein | TPSS/def2-SV(P) relaxed protein | B3LYP/def2-SV(P) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N | Fe | Fe | Fe | Fe/other | N | Fe | Fe | Fe | Fe/other | N | Fe | Fe | Fe | Fe/other | ||
| End-on NNH2 binding | ||||||||||||||||
| Fe1 | BS7-235 | 1.27 | 1.79 | 1.27 | 1.79 | 1.27 | 1.79 | |||||||||
| Fe2 | BS7-235 | 1.25 | 1.92 | 1.25 | 1.92 | 1.22 | 2.10 | |||||||||
| Fe3 | BS10-147 | 1.27 | 1.81 | 1.27 | 1.84 | 1.27 | 1.80 | |||||||||
| Fe4 | BS7-235 | 1.28 | 1.80 | 1.28 | 1.82 | 1.24 | 1.85 | |||||||||
| Fe5 | BS7-235 | 1.43 | 1.90 | S3A = 1.78 | 1.43 | 1.94 | S1A = 1.80 | 1.43 | 1.93 | S3A = 1.76 | ||||||
| Fe6 | BS10-147 | 1.26 | 1.86 | 1.26 | 1.83 | 1.26 | 1.86 | |||||||||
| Fe6(HCA) | BS10-135 | 1.26 | 1.85 | 1.25 | 1.84 | |||||||||||
| BS7-235 | 1.26 | 1.82 | 1.25 | 1.82 | ||||||||||||
| Fe6(HNNH2) | BS10-135 | 1.28 | 1.84 | 1.29 | 1.87 | |||||||||||
| BS10-147 | 1.28 | 1.84 | 1.28 | 1.84 | 1.30 | 1.88 | ||||||||||
| Fe6(S2B) | BS10-127 | 1.38 | 1.84 | S2B = 1.70 | 1.38 | 1.84 | S2B = 1.72 | 1.35 | 1.87 | S2B = 1.70 | ||||||
| Fe7 | BS7-235 | 1.26 | 1.85 | 1.26 | 1.85 | 1.25 | 1.84 | |||||||||
| Fe3(S2A) | BS7-235 | 1.42 | 1.93 | S2A = 1.73 | 1.41 | 1.95 | S2A = 1.76 | 1.41 | 1.97 | S2A = 1.73 | ||||||
| Fe2/4 | BS7-235 | 1.39 | 1.98 | 1.87 | S1A = 1.76 | 1.39 | 1.95 | 1.89 | S1A = 1.76 | 1.38 | 2.05 | 2.19 | S1A = 1.68 | |||
| Fe3/4 | BS7-235 | 1.31 | 1.83 | 1.76 | 1.32 | 1.86 | 1.78 | 1.26 | 2.06 | 1.97 | ||||||
| Fe2/6/7 | BS7-235 | 1.35 | 1.90 | 1.87 | 1.86 | 1.38 | 1.93 | 1.88 | 1.90 | 1.33 | 1.93 | 1.98 | 1.87 | |||
| Fe2/6(5) | BS10-147 | 1.39 | 1.88 | 1.87 | S2B = 1.76 | 1.42 | 1.92 | 1.88 | S2B = 1.77 | 1.37 | 1.72 | 1.92 | S2B = 1.72 | |||
| Fe3/7(2) | BS5-256 | 1.29 | 1.81 | 1.80 | 1.31 | 1.81 | 1.83 | 1.27 | 1.82 | 1.84 | ||||||
| Fe3/7(3) | BS7-235 | 1.31 | 1.90 | 1.86 | 1.32 | 1.91 | 1.86 | 1.25 | 2.02 | 1.86 | ||||||
| Fe4/5(2) | BS7-235 | 1.40 | 1.92 | 1.90 | S3A = 1.75 | 1.42 | 1.95 | 1.92 | S3A = 1.76 | 1.40 | 2.02 | 1.94 | S3A = 1.72 | |||
| Fe4/5(5) | BS7-235 | 1.28 | 1.81 | 2.18 | 1.29 | 1.81 | 2.20 | 1.27 | 1.81 | 2.21 | ||||||
| Fe2/3/6/7 | BS7-235 | 1.35 | 1.90 | 2.64 | 1.87 | 1.86 | 1.38 | 1.91 | 1.88 | 1.91 | 1.36 | 1.91 | 2.36 | 2.03 | 1.87 | |
| Fe2/4/5/6 | BS7-235 | 1.39 | 2.12 | 1.86 | 1.92 | 2.49 | 1.36 | 2.14 | 1.97 | 2.15 | 1.96 | 1.37 | 2.16 | 1.89 | 1.95 | 2.62 |
| Fe3/4/5/7 | BS7-235 | 1.35 | 2.43 | 1.93 | 2.07 | 1.96 | 1.35 | 1.92 | 2.02 | 1.97 | 1.33 | 1.93 | 2.22 | 1.90 | ||
| Side-on cis-HNNH binding | ||||||||||||||||
| Fe2Fe2 | BS10-147 | 1.32 | 2.13 | 2.03 | 1.31 | 2.12 | 2.11 | 1.30 | 2.13 | 2.04 | ||||||
| Fe4Fe4 | BS10-147 | 1.37 | 2.02 | 1.95 | 1.34 | 2.10 | 1.97 | 1.34 | 2.09 | 1.97 | ||||||
| Fe5Fe5 | BS10-146 | 1.33 | 2.02 | 2.02 | 1.33 | 2.07 | 2.00 | 1.31 | 2.04 | 2.01 | ||||||
| Fe6Fe6 | BS7-235 | 1.37 | 1.95 | 2.04 | S2B = 1.76 | 1.38 | 1.95 | 2.04 | S2B = 1.77 | 1.34 | 1.95 | 2.04 | S2B = 1.75 | |||
| Fe7Fe7 | BS7-235 | 1.38 | 1.92 | 1.97 | S5A = 1.80 | 1.38 | 1.92 | 1.98 | S5A = 1.81 | 1.33 | 2.08 | 1.96 | S5A = 1.78 | |||
| Fe2/3Fe6/7 | BS7-235 | 1.37 | 1.99 | 1.96 | 1.97 | 1.94 | 1.39 | 2.01 | 1.99 | 1.99 | 1.99 | 1.30 | 2.21 | 2.15 | 1.92 | |
| Fe2/6Fe3/7 | BS7-235 | 1.35 | 1.96 | 2.03 | 1.94 | 2.00 | 1.34 | 2.01 | 2.05 | 2.03 | 2.08 | 1.35 | 1.96 | 2.03 | 1.94 | 2.00 |
| Fe2/6Fe3/7tr | BS6-156 | 1.40 | 1.94 | 1.93 | 1.92 | 1.93 | 1.39 | 1.94 | 1.94 | 1.92 | 1.93 | 1.33 | 1.96 | 2.16 | 1.91 | 2.02 |
| Fe2/4Fe5/6 | BS2-234 | 1.39 | 1.93 | 1.90 | 1.89 | 2.03 | 1.40 | 1.94 | 1.97 | 1.96 | 2.01 | 1.38 | 1.98 | 1.91 | 2.00 | |
| Fe2/6Fe4/5 | BS3-134 | 1.40 | 1.87 | 1.89 | 1.92 | 1.92 | 1.39 | 1.93 | 1.95 | 1.96 | 1.96 | 1.38 | 1.91 | 1.89 | 1.91 | 1.90 |
| Fe2/6Fe4 | BS7-235 | 1.40 | 1.87 | 1.93 | 1.96 | 1.40 | 1.92 | 1.98 | 1.96 | 1.39 | 1.87 | 1.94 | 1.95 | |||
| Fe3/7Fe4/5 | BS2-234 | 1.40 | 1.95 | 1.94 | 1.97 | 1.95 | 1.40 | 1.95 | 1.94 | 1.98 | 1.95 | 1.33 | 2.19 | 1.95 | 2.20 | 1.97 |
| Fe2Fe7 | BS7-235 | 1.27 | 2.00 | 1.93 | 1.27 | 2.06 | 1.94 | 1.26 | 2.10 | 1.95 | ||||||
| Fe3Fe6 | BS10-147 | 1.28 | 1.85 | 1.92 | 1.28 | 1.87 | 1.96 | 1.26 | 1.86 | 1.93 | ||||||
| Fe2Fe6(3) | BS10-147 | 1.41 | 1.94 | 1.93 | S2B = 1.76 | 1.41 | 1.95 | 1.93 | S2B = 1.77 | 1.39 | 1.95 | 1.99 | S2B = 1.75 | |||
| Fe2Fe6(5) | BS7-235 | 1.29 | 1.93 | 1.88 | 1.29 | 1.90 | 1.92 | 1.26 | 2.10 | 1.92 | ||||||
| Fe3/7Fe3(2) | BS8-245 | 1.38 | 1.91 | 1.97 | 2.01 | 1.39 | 1.91 | 1.97 | 2.00 | 1.38 | 1.96 | 2.01 | 1.98 | |||
| Fe3Fe7(3) | BS5-256 | 1.29 | 1.88 | 1.87 | 1.29 | 1.86 | 1.88 | 1.30 | 1.91 | 1.89 | ||||||
| Fe45Fe5(2) | BS7-235 | 1.41 | 1.95 | 2.35 | 1.98 | 1.41 | 1.96 | 2.31 | 1.99 | 1.36 | 1.94 | 2.25 | 2.04 | |||
| Fe4Fe5(5) | BS2-234 | 1.29 | 1.82 | 1.87 | 1.29 | 1.87 | 1.82 | 1.29 | 1.83 | 1.90 | ||||||
| End-on trans-HNNH binding | ||||||||||||||||
| Fe2(trans) | BS10-147 | 1.26 | 1.94 | 1.25 | 1.96 | 1.23 | 2.13 | |||||||||
| Fe3(trans) | BS10-146 | 1.25 | 1.92 | 1.25 | 1.94 | 1.24 | 1.90 | |||||||||
| Fe4(trans) | BS7-235 | 1.26 | 1.88 | 1.26 | 1.89 | 1.24 | 1.90 | |||||||||
| Fe5(trans) | BS10-147 | 1.26 | 1.88 | 1.26 | 1.93 | 1.24 | 1.89 | |||||||||
| Fe6(trans) | BS10-147 | 1.25 | 1.91 | 1.26 | 1.93 | 1.23 | 2.07 | |||||||||
| Fe7(trans) | BS10-147 | 1.28 | 2.08 | 1.29 | 2.07 | 1.24 | 2.13 | |||||||||
| End-on cis-HNNH binding | ||||||||||||||||
| MoFe6(cis) | BS7-235 | 1.32 | 2.19 | 2.11 | 1.32 | 2.17 | 2.27 | 1.32 | 2.20 | 2.11 | ||||||
| Fe2(cis) | BS10-147 | 1.26 | 1.92 | 1.26 | 1.93 | 1.23 | 2.10 | |||||||||
| Fe3(cis) | BS10-146 | 1.26 | 1.89 | 1.26 | 1.93 | 1.25 | 1.88 | |||||||||
| Fe4(cis) | BS7-235 | 1.27 | 1.87 | 1.28 | 1.87 | 1.26 | 1.89 | |||||||||
| Fe5(cis) | BS7-235 | 1.25 | 2.40 | 1.24 | HNNH released | 1.23 | HNNH released | |||||||||
| Fe6(cis) | BS10-135 | 1.25 | 1.90 | 1.26 | 1.91 | 1.24 | 1.94 | |||||||||
| Fe7(cis) | BS7-235 | 1.29 | 1.88 | 1.29 | 1.89 | 1.28 | 1.90 | |||||||||
Three geometries are given: TPSS-D3/def2-SV(P) optimised with surroundings fixed, TPSS-D3/def2-SV(P) optimised with surroundings relaxed, and B3LYP-D3/def2-SV(P) optimised with surroundings fixed. BS indicates the studied BS state. The “other” columns give N–S distances, if they are shorter than 2.0 Å. The Fe–N distances are given in the order indicated by the name of the structure