| DNIC | Dinitrosyl iron complex |
| NO | Nitric oxide |
| MNIC | Mononitrosyl iron complex |
| RRE | Roussin’s red ester |
| TRIR | Time-resolved infrared |
| EPR | Electron paramagnetic resonance |
| DFT | Density functional theory |
| MLCT | Metal-to-ligand charge transfer |
| SVD | Singular value decomposition |
| IR | Infrared |
| OPA | Optical parametric amplifier |
| PCM | Polarized continuum model |