Fine and hyperfine structure of the 22 P term of7Li; determination of the nuclear quadrupole moment

Microwave transitions between the Zeeman split doublet states 2² P _1/2 and 2² P _3/2 of⁷Li have been measured using the optical double resonance method. The fine structure separation was determined to bev _fs=10.053.184(58) MHz. The hyperfine structure was well resolved and led to considerably improved precision of the diagonal coupling constantsa _1/2=45.914(25) MHz,a _3/2=?3.055(14) MHz,b=?0.221(29) MHz. Furthermore, the contact, spin dipolar and orbital magnetic hyperfine constants are evaluated using additional results from level crossing experiments, which are more sensitive on the non-diagonal magnetic hyperfine constanta _3/2,1/2. The results are in good agreement with recent theoretical calculations. The nuclear quadrupole moment is derived fromb to beQ(⁷Li)=?41(6) mbarn.