Magnetic Hyperfine Structure of Lithium

Abstract

For the first time a spin-polarized extended Hartree-Fock calculation on a three-electron system, Li, is reported. The calculations are discussed with primary emphasis on the hyperfine splitting spectrum which is determined by the spin density at the nucleus, $Q\left(0\right)=\frac{〈\psi \left|\Sigma {\mathrm{i}}^{}{\hat{s}}_z\mathrm{}\left(i\right)\mathrm{}\delta \left(r_{\mathrm{i}}\right)\right|\psi 〉}{S}$. We calculate $Q\left(0\right)\mathrm{}$ for the ground state to be 0.2403, as compared with the experimental value of 0.2313.