Conduction-electron spin resonance in metallic lithium

Conduction-electron spin resonance in metallic lithium has been studied by second-derivative techniques over the temperature range 4.2-300°K. The ultrapure specimens, which were refined by precipitation out of liquid-ammonia solutions, gave Dysonian-shaped lines of width 18 ± 2 mG. The corresponding relaxation time, $T_2=(3.2\mathrm{}\pm 0.4)\times {10}^{-6\mathrm{}}$ sec, is about 30 times as large as that expected from spin-orbit coupling but agrees roughly with that deduced from the spin-current mechanism of relaxation. Within experimental uncertainty, $T_2$ was almost independent of temperature. The observed $g$ shift was very small, in agreement with previous work.