Table 6. endo-Nitrito Linkage Isomer Populations (P) and Reaction-Cavity Volumes (Vcav) per Complex Molecule Calculated for the Ni-2a Complex during Photocrystallographic Experimentsa.
| compound | T (K) | P (%) | Vcav (Å3) |
|---|---|---|---|
| Ni-2a | 140b | 0.0 | 39.4 |
| 140 | 26.2(2) | 38.8 | |
| 160 | 34.3(3) | 33.5 | |
| 180 | ≈3c | 31.7 | |
| 200 | 0.0 | 41.09 | |
| Ni-2bb | 160b | 0.0 | 27.7d/32.7e |
| 160 | 36(1)d/37(1)e | 28.1d/30.9e | |
| 240 | 0.0 | 30.5d/34.4e |
a
Calculated before and after irradiation during structure thermal relaxation. Cavity volumes were computed with the MERCURY program (probe radius of 1.2 Å and grid spacing of 0.1 Å). Note that several values are provided for the Ni-2b crystal structure. Note that the standard deviation on Vcav was estimated to be ca. 0.5 Å3.16
b
Before irradiation.
c
Roughly estimated based on the generated residual density maps.
d
Symmetry-independent molecule A.
e
Symmetry-independent molecule B.