Introduction To Dynamic Spin Chemistry: Magnetic Field Effects Upon Chemical And Biochemical Reactions (world Scientific Lecture And Course Notes In Chemistry, Vol. 8)

Introduction to Dynamic Spin Chemistry Magnetic Field Effects on Chemical and Biochemical Reactions WORLD SCIENTIFIC LECTURE AND COURSE NOTES IN CHEMISTRY Editor-in-charge: S. H. Lin VOl. 1: Monte Carlo Methods in Ab lnitio Quantum Chemistry B. L. Hammond, W. A. Lester, Jr. & P. J. Reynolds VOl. 2: Quantum chemistry Aided Design of Organic Polymers: An Introduction to the Quantum Chemistry of Polymers and Its Applications J. -M. Andre, J. Delhalle & J. -L. Bredas VOl. 4: The Physical Chemistry of Biopolymer Solutions: Application of Physical Techniques to the Study of Proteins and Nuclei Acids R. F. Steiner& L. Garone VOl. 5: Theoretical HeterogeneousCatalysis R. A. van Santen Vol. 6: Density Matrix Method and Femtosecond Processes S. H. Lin, R. Alden, R. Islampour, H. Ma & A. A. Villaeys VOl. 7: Spectroscopy and Dynamics of Orientationally Structured Adsorbates V. M. Rozenbaum & S. H. Lin voi. a: Introduction to Dynamic Spin Chemistry: Magnetic Field Effects on Chemical and Biochemical Reactions H. Hayashi World Scientific Lecture and Course Notes in Chemistry - Vol. 8 Introduction to Dynamic Spin Chemistry Magnetic Field Effects on Chemical and Biochemical Reactions Hisaharu Hayashi RII = ml)I,m 3 , PII,m p = J I ( I + 1) - m, (m, + 1) 1 , m+l>, (1- 4 0 ~ ) r(I,ml>= J ~ ( ~ + l ) - m , ( m , - l ) ~ , m ~ l > . (1-40d) Table 1-1 shows the g N values of typical nuclei together with their I values and natural abundance. It is worth while to remark from this table that many nuclei such as I2C and I6C have no spin ( I = 0). The isotopes with and without spin, therefore, are called “magnetic and non-magnetic isotopes”, respectively. Even now, it is very difficult to explain theoretically the observed I and g N values. This is one of the frontiers of modem physics. Solutions to the Problems 1-1. From Eq. (1-24), b ] = [g [Sl= [A m21. 1-2. [I] = [ r m,v] = [m] [kg] [ d s ] = [kg m2 s-*] [s] = [J s]. 1-3. ,uB =- eA 2m. = 1 . 6 0 2 1 8 ~ 1 0 - ’ ~*C1 . 0 5 4 5 7 ~ 1 0 Js - ~ ~= 9.2740x10-24 Jcs/kg. 2 9.10939 x kg Using [C] = [As], [JCsikg] = [JAs’ikg]. Using [A] = [kg/s2Tl from Eq. (1-6b), [JAs2/kgl = [Jl [kg/s2Tl [s2/kgl = [J T-’]. Thus, ,UB = 9 . 2 7 4 ~ 1 0J-T-I. ~~ 1-4. If‘m, of the above p~ calculation is replaced by mp (= 1.67262 X lO-”kg), the pNvalue can be obtained to be 5 . 0 5 0 7 9 ~ 1 0 ~ ~T-I. ’J 7 Table 1-1. Nuclear spin properties. Isotope Natural Spin (4 (gN) 99.985 0.015 112 1 5.58570 0.85744 98.90 1.10 0 - Abundance (%) 'H *H I2C l3C __ g-factor 112 1 112 ______ 1.40482 0.40376 4.56638 I4N 'N 99.634 0.366 l6O 99.762 0.038 0.20