电子磁共振原理(英文版)

Contents Introduction 1 Origin of EMR 1 Experimental apparatus 3 Microwave source 4 Resonant cavity and coupling system 5 Magnet 10 Detection system 12 Data treatment system 12 Target of research 13 Prospects for future 13 References 14 Theoretical basics 16 Phenomenal description of EMR 16 Angular momentum and magnetic moment 17 Orbital motion of electron and its magnetic moment 17 Eigen motion of electrons and its magnetic moment 20 Spin angular momentum and magnetic moment of atomic nucleus 23 Electric quadrupole moment of atomic nucleus 25 Unit of magnetic field 26 The interaction between external fields and magnetic moment 28 Interaction of magnetic moment with electromagnetic field in the external magnetic field 30 Interaction of nuclear magnetic moment with electron magnetic moment in the external magnetic field 33 References 34 Further reading 34 g-Tensor theory 35 Landé factor 35 Matrix presentation of g-tensor 37 g-Tensor of colour center (cubic symmetry and uniaxial symmetry system) 37 The g-tensor of nonaxisymmetric (lower than uniaxial symmetry) system 39 _x00C_VIII Contents g-Tensor of irregular orientation system 46 g-Tensor of axisymmetric system 46 g-Tensor of nonaxisymmetric system 50 References 52 Further reading 52 Isotropic hyperfine structure 53 Theoretical exploration of hyperfine interaction 53 Dipole–dipole interaction 53 Fermi contact interaction 54 Energy operator of isotropic hyperfine interaction 55 Spin operator and hamiltonians 55 Zeeman interaction of electrons and nuclei 57 Spin hamiltonian of isotropic hyperfine interaction 59 Spectral isotropic hyperfine structure 60 System with one magnetic nucleus and one unpaired electron 60 Multimagnetic nuclei with one unpaired electron system 65 Hyperfine splitting arising from other magnetic nuclei 71 Encountered problems in isotropic radical spectra 75 Hyperfine structure of organic π-free radical spectrum 76 Hyperfine coupling constant of organic π-radical 76 McConnell semiempirical formula 76 Hückel molecular orbital (HMO) theory 77 Calculation of probability density distribution of unpaired electron 79 The Q value of the radical with fully symmetrical structure 85 Hyperfine coupling constant a value of the even alternant hydrocarbons 86 Hyperfine coupling constant a value of the even alternant heterocyclic hydrocarbons 89 Hyperfine coupling constant a value of the odd alternant and nonalternant hydrocarbons 90 Mechanism of hyperfine splitting in the spectrum of conjugated systems 91 “Electronic correlation” effect 91 The sign of proton hyperfine splitting constant 93 Negative spin density 96 About the Q value problem 96 Hyperfine splitting and hyperconjugation effect of methyl protons 98 Hyperfine splitting of other (non-proton) nuclei 101 Hyperfine splitting of 13C nucleus 101 _x00C_Contents IX 4.6.2Hyperfine splitting of 14N nucleus1034.6.3Hyperfine splitting of 19F nucleus1044.6.4Hyperfine splittings of 17O and 33Snuclei105References 105 Further readings 106 Anisotropic hyperfine structure 107 Anisotropic hyperfine interaction 107 Matrix interpretation of anisotropic hyperfine interaction 110 Example demonstration 116 Anisotropic hyperfine coupling tensor and structure of radical 122 Hyperfine coupling tensor of central atom 122 Hyperfine coupling tensor of α-hydrogen atom 127 Hyperfine coupling tensor of β-hydrogen atom 130 Hyperfine coupling tensor of σ-type organic radicals 132 Anisotropy of the combination of g-tensor and A-tensor 133 Anisotropy of A tensor in the irregular orientation system 133 References 135 Further readings 136 Fine structure 137 Zero-field splitting 138 Spin hamiltonian of two-electron interaction 140 Exchange interaction of electron spin 140 Dipole interaction of electron–electron 144 The triplet molecule (S = 1) system 153 Energy levels and wave functions of triplet molecules under the action of external magnetic field 153 Examples of triplet state excited by light 156 Examples of thermal excitation triplet state 157 Examples of other excited triplet 159 Examples of ground triplet state 159 Triplet system of irregular orientation 162 Biradical 166 References 169 Further reading 170 Relaxation and line shape and linewidth 171 Model of spin relaxation 171 Spin temperature and boltzmann distribution 171 Spin particle transition dynamics 173 Mechanism of the effect of relaxation time τ1 on linewidth 175 _x00C_X Contents 7.1.4Magnetization in static magnetic field1777.1.5Bloch equation in the static magnetic field1787.1.6 Bloch equation in the static magnetic field coupled with the oscillating magnetic field 180 7.1.7Stationary solutions of bloch equation1817.2Shape, width, and intensity of spectral line1827.2.1Line shape function 1827.2.2Linewidth 1867.2.3Line broadening 1887.2.4Line intensity 1887.3Dynamic effects of line shape 1897.3.1Generalized bloch equation 1897.3.2Chemical exchange broadening mechanism1937.3.3 Mechanism of the spectral lines broadening caused by physical motion 200 Saturation transfer of spectra 214 Intensity of signal dependent on time 214 Free radical concentration changes with time 214 Chemical-induced dynamic electron polarization (CIDEP) 215 References 217 Further readings 218 8Quantitative determination 2208.1Main factors of influence for quantitative determination2218.1.1Factors of instrument 2218.1.2Influence of operating factors 2288.2Selection and preparation of standard samples 2358.3Key parameters and its effect on the intensity of EMR signal2378.4Achievable accuracy of quantitative determination 239References 240 Paramagnetic gases and inorganic radicals 242 Spectra of paramagnetic gases 242 Monoatomic paramagnetic gases 242 Diatomic paramagnetic gas 245 Gaseous molecules of triatom and polyatom 256 Expanding of EMR technique for study on paramagnetic gas 257 9.2.1Laser electronic magnetic resonance2579.2.2Magnetic resonance induced by electron2579.3Inorganic radicals 2589.4Point defects in solid states 2619.5Spectra of conductor and semiconductor265Contents XI 9.6 Structure of a molecule structure of a molecule estimated from the data of EMR 268 References 269 Further readings 272 10Ions of transition elements and their complexes 27310.1Electron ground state of transition element ion 27310.2Orbital degeneracy is rescinded in ligand field 27510.3Electric potential of ligand field 27810.4Energy-level splitting of transition metal ion in ligand field28210.4.1P-state ion in octahedron Field (L = 1) 28210.4.2D-state ion 28310.4.3About F-state ion 28610.5Spin–orbit coupling and spin hamiltonian 28810.6Ground-state ion with orbital nondegeneracy 29410.6.1D-state ions of ground-state orbital nondegenerate 29510.6.2F-state ions of ground-state orbital nondegenerate 29810.6.3S-state ions of the ground-state orbital nondegenerate30510.7Ground-state ions with orbital degeneracy 31010.7.1D-state ions 31010.7.2F-state ions 31610.7.3Jahn–Teller distortion 32010.7.4The palladium group (4d) and platinum group (5d) ions32110.8EMR spectra of rare earth Ions 32110.8.1Lanthanide ion 32110.8.2Actinide ions 32310.9EMR spectra of transition metal complexes 324References 325 Further readings 327 Appendix 1: Extension and expansion of EMR 328 Appendix 2: Mathematical preparation 399 Appendix 3: Angular momentum and stable-state perturbation theory in quantum mechanics 421 Appendix 4: Fundamental constants and useful conversion actors 442 Appendix 5: The natural abundance, nuclear spin, nuclear magnetogyric ratio of some magnetic nuclei and their hyperfine coupling parameters 445 Index 451_x00C_