The visible emission spectrum of iodine

The emission spectrum of iodine has been photographed in the visible region at high resolution, and 16 bands of the $\text{B0}{}^{\mathrm{+}}\text{u(}{}^3\text{Π}\text{)] → X0}{}^{\mathrm{+}}\text{g(}{}^1\text{Σ}\text{)]}$ system have been rotationall analyzed. Centrifugal distortion constants for the B state are calculated from the empirical (RKR) potential curve using a method which employs semiclassical phase integrals. The results of the rotational analysis are processed together with earlier results to yield improved spectroscopic parameters for the B state, valid for 3 < v′ < 40.