Millimeter-wave rotational spectrum and molecular constants of diatomic gallium bromide

Gas-phase spectra of four isotopic species of GaBr have been detected in the millimeter wavelength region. The molecules were produced by a flame reaction of gallium and bromine at 1000° C. From the rotational spectra molecular constants have been determined for ⁶⁹Ga⁷⁹Br,⁶⁹Ga⁸¹Br,⁷¹Ga⁷⁹Br,⁷¹Ga⁸¹Br. The equilibrium internuclear distance is r_e = 2.3524907(82).