Radio-Frequency and Microwave Spectra of LiBr by the Molecular-Beam Electric-Resonance Method

Abstract

The molecular-beam electric-resonance technique has been used to obtain dipole moments μv, quadrupole interaction constants of bromine (eqQ)v, spin—rotation interaction constants cBr, and rotational constants for 6Li79Br and 6Li81Br in several of the lower vibrational levels. The observation of J=1 radio-frequency spectra for three or more vibrational states led to the following values: 6Li79Brμv=7.22624+0.08318(v+12)+0.00057(v+12)2±0.001 D,(eqQ)v=37.015+2.918(v+12)−0.039(v+12)2±0.005 Mc/sec,cBr=9.2±0.2 kc/sec. 6Li81Brμv=7.22611+0.08312(v+12)+0.00060(v+12)2±0.001 D,(eqQ)v=30.912+2.442(v+12)−0.034(v+12)2±0.005 Mc/sec,cBr=9.9±0.2 kc/sec.The observation of J=1→J=0 microwave transitions yielded the following rotational constants: Li796Br (Mc/sec)Li816Br (Mc/sec)B0=19 090.296±0.006,B0=19 057.005±0.006,B1=18 882.800±0.009,B1=18 850.050±0.020,B2=18 677.242±0.055.B2=18 645.035±0.217.