The resolved super-hyperfine splitting of anisotropic ESR spectra of both studied compounds was firstly observed. The electron spin resonance (ESR) spectra of niobocene and vanadocene dichlorides were studied on the title compounds prepared as magnetically diluted species in polycrystalline form. Superhyperfine Splitting Septet. Triplet: hyperfine splitting. ESR Experimental technique 13 2. Triplet: hyperfine splitting. The structure observed in the perpendicular region of the spectra is due to nitrogen superhyperfine splitting of the ligands. vealed that the superhyperfine splitting of the g, ESR signal of ferrousNO complexes is dependent on the conformation of the protein and thus the interaction of the axial ligands with the heme iron. Ligand superhyperfine splitting in the low pH form of the esr signal of Cu(II)-dog albumin were not resolved. Spin-spin interaction of electrons 10 1.3. Doublet: superhyperfine splitting. If we are dealing with a single crystal, then there is only one EPR line (all molecules have the same orientation), which might be split up by (super)hyperfine … 19. The EPR measurements showed that the superhyperfine splitting is anisotropic and that the number of observable lines (17 at 9 Gc/sec along ) and the splitting of the lines is field-dependent. 5. IF= ½, so 2(6)(1/2) + 1 =7 Triplet: superhyperfine splitting.IN= 1, so 2(1)(1) + 1 = 3 So, spending most time on F’s, less on N. Nonet: hyperfine splitting. The spin densities in the ligand s and p valence orbitals and the p/s ratios were computed where possible. interaction) or with the nucleus of a ligand (superhyperfine interaction), is of no concern for the simulation, since they are treated in the same way. The greater the covalency, the greater is the hyperfine splitting. Spin - lattice Relaxation 12 1.3.3. The greater the covalency, the greater is the hyperfine splitting. In contrast, the esr spectra of Vu(II)-dog serum albumin complex showed a transition from a low pH form to a high pH form as the pH was increased to 9.5. IN= 1, so 2(4)(1) + 1 =9 Pentet: superhyperfine splitting. The phenomena of saturation and relaxation 10 1.3.1. The phenomenon of saturation 11 1.3.2. It is possible for the unpaired electron to spend differing amounts of time on different nuclei. ESR METHODS OF STUDY FREE RADICALS AND ANTIOXIDANTS 15 2.1. The value of 14 × 10 −4 cm −1 and the presence of three peaks for the nitrogen superhyperfine structure of the complex are in accordance with expectations for two N donors per copper(II) ions [52, 53]. Superhyperfine Splitting Examples: Sextet Septet Octet Superhyperfine splitting is direct evidence for COVALENCY! An impurity ion centre identified as Se− has been produced by irradiation with blue light at − 100°C in AgCl:Se, Cd. Octet It is possible for the unpaired electron to spend differing amounts of time on different nuclei. Spin - spin Relaxation 13 1.4. Superhyperfine splitting of the EPR spectra in this system was previously observed only at the orientation of the magnetic field B along the symmetry axis of the crystal . Superhyperfine splitting 9 1.2.6. These spectral changes were found to be reversible upon lowering the pH. The g and superhyperfine splitting tensors are shown to be consistent with having the odd electron in an antibonding orbital of a 1g symmetry made up largely from the metal d z 2 orbital. Doublet: superhyperfine splitting. Examples: Sextet Superhyperfine splitting is direct evidence for COVALENCY! 1.2. IH= 1/2, so 2(4)(1/2) + 1 = 5 So, spending most time on N’s, less on H. Superhyperfine coupling overlapping pentet of pentets.