Abstract
The rotational spectra of
79Br and
81Br-bromobenzene have been remeasured, and spectra for eight singly substituted
13C isotopomers have been measured for the first time using Fourier-transform microwave spectroscopy. This has made possible a determination of the heavy atom structure using both Kraitchman substitution (
r
s) and inertial fit analyses (
r
0). The experimental structures have been compared with ab initio calculations at the MP2/6-311++G (2df,2p) level as a means of confirming the experimental results. The experimental rotational constants were found to be
A=5667.750(52)
MHz,
B=994.9018(2)
MHz, and
C=846.2567(2)
MHz for
79Br bromobenzene and
A=5667.730(54)
MHz,
B=984.7084(2)
MHz, and
C=838.8702(2)
MHz for
81Br bromobenzene. The quadrupole coupling constants were further refined to
χ
aa=556.700(16)
MHz,
χ
bb=−292.86(8)
MHz, and
χ
cc=−263.84(3)
MHz for the
79Br species and
χ
aa=465.039(17)
MHz,
χ
bb=−244.63(8)
MHz, and
χ
cc=−220.41(6)
MHz for the
81Br species.