Diode laser spectroscopy of the ν3 and ν2 bands of FHF− in 1300 cm−1 region

The ν3, ν2, and ν1+ν3−ν1 bands of a linear molecular anion FHF− have been detected by diode laser spectroscopy in 1300 cm−1 region. The previously reported 1848 cm−1 band [K. Kawaguchi and E. Hirota, J. Chem. Phys. 84, 2953 (1986)] was reassigned to the ν1+ν3 combination band. Analysis of the observed spectra gave the fundamental frequencies ν1=583.0539(13), ν2=1286.0284(22), and ν3=1331.1502(7) cm−1 with three standard deviations in parentheses. From the rotational constants obtained, the equilibrium F–F internuclear distance was calculated to be 2.277 71(7) A.