“…The first term, 2Pe, describes the interaction of the unpairedelectron with the external magnetic field: Y e = ,KS*g*H (2) where S is the vector spin of the electron, / 3 the Bohr magneton and 535 atomic hydrogen with an electron occupying a 1s orbital about the nucleus of magnetic moment, p N . We have for the hyperfine interaction, a, in terms of the electron wave function, $ ( I ) , ( H O ) = ',BngPPN $ 4 8 (O) ( 5 ) P is the Bohr magneton.…”