5 State Reference A$_{⊥}$ (MHz) A$_{‖}$ (MHz) G$_{⊥}$ G$_{‖}$ W$_{d}$ (10 $^{25}$)Hz /e cm W$_{P,T}$ (KHz) W$_{P}$ (KHz) $^{2}$Π$_{1}$$_{/}$$_{2}$ [2] -8990 10990 -0.326 0.040 1.4 55 -0.72 [4] 7200 ± 150 10300 ± 800 [28] 1.5 [1] (a) -7460 8690 -0.269 0.034 1.0 51 -0.65 [1] (b) -8240 9550 -0.438 0.114 1.8 99 -1.25 This work -6859.6 9726.9 -0.319 0.082 1.6 74.95 -0.99 A $^{2}$Σ+ 1 / 2 [4] − 1200 ± 300 3000 ± 2500 This work 1720.8 3073.3 2.417 1.92 2.5 123.7 -1.588 TABLE III: Parameters of the spin-rotational Hamiltonian H sr for $^{2}$Π$_{1}$$_{/}$$_{2}$ and A $^{2}$Σ + 1 / 2 states of PbF molecule